Evident Scientific

Evident phased array instruments provide precise measurement with the most reliable results. Our range of phased array devices produce accurate, detailed cross-sectional pictures of internal structures at fast inspection speeds.

OmniScan X3 Series

Every flaw detector in the OmniScan™ X3 series is a complete phased array toolbox. Innovative TFM and advanced PA capabilities help you identify flaws with confidence while powerful software tools and simple workflows improve your productivity.

OmniScan SX

The single group, lightweight OmniScan SX flaw detector features an easy-to-read 8.4-inch (21.3 cm) touch screen and provides cost-effective solutions. The OmniScan SX comes in two models: the SX PA and SX UT. The SX PA is a 16:64PR unit, which, like the UT-only SX UT, is equipped with a conventional UT channel for P/E, P-C, or TOFD inspections.

FOCUS PX

The scalable FOCUS PX acquisition unit and Focus PC software incorporates the latest phased array technology for easy integration with automated and semiautomated inspection systems. The solution significantly improves SNR and inspection speeds. Available are the optional software development kits, FocusControl and FocusData

Phased Array Software

OmniPC 5 Software

OmniPC analysis software is the computer-based companion software for the OmniScan X3 flaw detector. An inspection tool created by inspectors, OmniPC software provides the power and performance to handle all your basic data analysis and reporting needs.

WeldSight

WeldSight™ software’s comprehensive acquisition and analysis tools enable you to engineer compliant and repeatable advanced phased array (PA), ultrasonic testing (UT), and time-of-flight diffraction (TOFD) weld inspections.

TomoView Software

TomoView is a powerful and flexible PC-based software used for design, data acquisition, visualization, and analysis of ultrasonic signals.

Evident full range of portable ultrasonic flaw detectors (UT) provides unmatched capabilities for locating discontinuities and other flaws. A wide range of software options is available for enhanced flaw detector inspection. 

OmniScan X3 Series

Every flaw detector in the OmniScan™ X3 series is a complete phased array toolbox. Innovative TFM and advanced PA capabilities help you identify flaws with confidence while powerful software tools and simple workflows improve your productivity.

EPOCH 650

The EPOCH 650 is a conventional ultrasonic flaw detector with excellent inspection performance and usability for a wide variety of applications. This intuitive, rugged instrument is a continuation of the popular EPOCH 600 flaw detector with additional capabilities.

EPOCH 6LT

The EPOCH 6LT portable ultrasonic flaw detector is optimized for one-handed operation and delivers excellent performance in rope access and high-portability applications. Lightweight with an ergonomic design, the instrument fits securely in a user’s hand or can be strapped to the leg for rope access applications.

OmniScan SX

The single group, lightweight OmniScan SX features an easy-to-read 8.4 inch (21.3 cm) touch screen and provides cost-effective solutions. The OmniScan SX comes in two models: the SX PA and SX UT. The SX PA is a 16:64PR unit, which, like the UT-only SX UT, is equipped with a conventional UT channel for P/E, P-C or TOFD inspections.

Advanced portable eddy current (EC) flaw detectors inspect metallic parts and perform highly reliable flaw detection of surface and near-surface defects. A full range of portable flaw detectors is available to serve the broadest range of applications. Eddy current probes generate magnetic fields that induce current that flows in a test piece influencing the magnetic field and magnitude and phase of voltage in the coil. Applications include the detection of surface or near-surface defects, alloy sorting, and the inspection of bolt holes.

NORTEC 600

The NORTEC 600 incorporates high-performance eddy current flaw detection into a compact, durable unit. With its vibrant 5.7 inch VGA color display and true full-screen mode, the NORTEC 600 produces user-selectable, highly contrast eddy current signals.

OmniScan MX ECA/ECT

Performs eddy current array testing inspections. The test configuration supports 32 sensor coils (up to 64 with an external multiplexer) working in bridge or transmit-receive mode. The operating frequency ranges from 20 Hz to 6 MHz with the option of using multiple frequencies in the same acquisition.

Rotating Bolthole Scanners

The high performance eddy current bolt hole scanners are available for use with Nortec Eddy Current flaw detectors. Features include speed ranges from 600 to 3000 rpm, frequency ranges from 100 Hz to 6 MHz, multiple connector types, and multiple probe types, our scanners offer a full range of application solutions.

Evident is a leading source of ultrasonic thickness gauges for accurately measuring the thickness of many types of material. Our digital thickness gauges offer a range of features for advanced performance. Explore different options to suit your application needs, from simple handheld gauges to advanced models. All of our ultrasonic thickness gauges can measure thickness from one side of a part. An ultrasonic thickness gauge can measure most engineering materials, including plastics, metals, metal composites, rubber, and internally corroded materials. 

39DL PLUS

The 39DL PLUS™ ultrasonic thickness gauge redefines efficiency and connectivity in the nondestructive testing industry with ultra-fast scanning speeds and fully integrated wireless connectivity in a rugged handheld design. Building on the proven performance and versatility of its predecessor, the 39DL PLUS gauge provides a digital inspection workflow that saves inspectors time in precision and corrosion thickness inspections.. 

72DL PLUS

The 72DL PLUS™ advanced ultrasonic thickness gauge delivers precision thickness measurements at high speed in a portable, easy-to-use device. Compatible with single element transducers up to 125 MHz, this innovative thickness measuring tool is ideally suited to determine the thickness of ultra-thin materials, including multilayer paint, coatings, and plastic. It can simultaneously display the thickness of up to 6 layers. Collect more inspection data to better control product quality. The PC interface application offers data creation, management, sharing, and analysis tools to empower data-driven decisions on the manufacturing production floor. Monitor thickness trends, spot quality issues, and generate reports to help maintain consistent product quality and improve processes.

45MG

The 45MG advanced ultrasonic thickness gauge is packed with standard measurement features and software options. This unique thickness measuring tool is compatible with our complete range of dual element and single element thickness gauge transducers.

27MG

The 27MG is a basic ultrasonic thickness gauge designed to make accurate measurements from one side on internally corroded or eroded metal pipes and parts. It is lightweight, durable, and ergonomically designed for easy, one-hand operation.

Magna-Mike 8600

The Magna-Mike is a Hall Effect thickness gauge that uses a magnetic probe to perform accurate measurements on nonferrous and thin materials such as plastic bottles.

35 RDC

The 35RDC is a simple Go/No-Go ultrasonic gage designed to detect subsurface defects caused by impact damage on aircraft composite structures.

Transducers and Accessories

Evident offers a variety of single and dual element transducers and accessories for precision and corrosion thickness gauging.

Evident has a wide range of scanners to address fabrication or maintenance weld inspections needs. We have solutions for small pipes up to flat plates with the capacity to hold multiple probes for complete weld volume coverage. Whether you choose a motorized or manual option, our scanners offer versatility, dependability, and repeatability.

Wire Encoder

Acquire high-quality phased array data with high positioning accuracy thanks to the wire encoder’s simple streamlined design, enabling you to focus on handling the probe. It installs quickly on both ferromagnetic and nonferromagnetic surfaces.Acquire high-quality phased array data with high positioning accuracy thanks to the wire encoder’s simple streamlined design, enabling you to focus on handling the probe. It installs quickly on both ferromagnetic and nonferromagnetic surfaces.

HST-Lite Scanner

The new HST-Lite scanner is the perfect choice for cost-effective, one-channel TOFD inspections when signal quality is important. The combination of magnetic wheels and spring-loaded probe holders offer the stability required to perform high quality, one-line inspections. The scanner can be operated using only one hand, and will attach to ferromagnetic surfaces even when in an upside-down position.

Mini-Wheel Encoder

The mini-Wheel Encoder is used for the positioning and dimensioning of defects in the scan axis. It can synchronize data acquisition with probe movement. It is also waterproof and compatible with Olympus standard PA wedges.

COBRA Scanner

The COBRA™ manual scanner combined with the OmniScan X3 flaw detector is used to perform circumferential welding inspections on small-diameter pipes. The COBRA small-diameter scanning unit can hold two PA probes to inspect pipes with ODs ranging from 0.84 to 4.5 in.

HSMT-Compact Scanner

The HSMT-Compact is a manual one-axis encoded scanner. In particular, it is light and small, and also versatile. It can be used (with up to 4 probes) on plates and for circumferential scans on pipes as small as 4.5 in. OD pipes.

HSMT-Flex Scanner

The HSMT-Flex is intended for manual one axis encoded inspection of circumference welds on pipes of 4.5 in. OD and greater. The scanner can be fitted with up to 8 probes using optional probe holders, thanks to its capacity to bend in the center.

HST-X04

The HST-X04 time-of-flight diffraction (TOFD) manual scanner offers an efficient, low-cost, and versatile weld inspection solution.

VersaMOUSE Scanner

The VersaMOUSE™ is a scanner designed for linear encoded scans with a phased array probe. The integrated indexing button makes it ideal for 2-D mapping applications such as CFRP flat panel and corrosion inspections. The VersaMOUSE can perform an encoded one-line scan, followed by indexing of the position in the perpendicular direction. Another one-line scan can then be performed and juxtaposed to the previous scan. This process is repeated to produce a complete 2D map of the area of interest.

Corrosion mapping is a highly demanding application that requires the capability to precisely encode the probe’s position in up to two axes. The scanners can be mounted on pipes and flat surfaces and are easy to use for fast detection of defects from manufacturing-induced lamination to in-service wall thickness reduction.

HydroFORM Scanner

An easy-to-deploy 2-axis encoding PA solution, the HydroFORM semiautomated scanner enables fast and reliable high-resolution data acquisition of large surfaces. To ease raster scanning, it’s equipped with X and Y encoders, a unique water column system, and coupling check and position indicators.

FlexoFORM

The innovative FlexoFORM scanner makes challenging pipe elbow corrosion inspection easier. The scanner's flexible phased array technology makes it possible to use a single probe to cover the entire range of pipe elbow diameters.

SteerROVER

The SteerROVER is a fully automated, steerable motorized 2-axis scanner capable of performing corrosion mapping in remote locations. The SteerROVER scanner, when fitted with a motorized raster arm, is a powerful solution for corrosion inspection in remote locations. Increase your ability to keep the scanner properly aligned by adding the optional RECON camera kit.

MapSCANNER

The MapSCANNER is a semiautomated, 2-axis corrosion inspection scanner. When combined with the HydroFORM or Dual Linear Array (DLA) phased array corrosion mapping solutions, it is a powerful, efficient tool for C-scan imaging of remaining wall thickness and mid-wall anomalies.

MapROVER

The MapROVER is a fully automated, motorized 2-axis corrosion mapping scanner. A combined MapROVER and HydroFORM™ corrosion mapping system offers a powerful and efficient solution, enabling PA imaging of remaining wall thickness and midwall anomalies. For high-temperature applications, the MapROVER HT scanner is equipped with a cooling system that enables automated corrosion mapping on surfaces as hot as 350°C (662 °F).

ChainSCANNER

The ChainSCANNER provides a manual pipe-inspection solution for pipes between 1.75 to 38 in. OD. The scanner, held by chain links instead of magnetic wheels is well suited for weld or corrosion inspection on different type of materials. UT, TOFD, PA.

GLIDER Scanner

The GLIDER scanner is a 2-axis (X-Y) encoding scanner for the manual inspection of slightly curved or flat composite surfaces. The scanner, held by suction cups is well suited for raster scanning. Technologies: ECA, EC, UT, PA.

VersaMOUSE Scanner

The VersaMOUSE™ is a scanner designed for linear encoded scans with a phased array probe. The integrated indexing button makes it ideal for 2-D mapping applications such as CFRP flat panel and corrosion inspections. The VersaMOUSE can perform an encoded one-line scan, followed by indexing of the position in the perpendicular direction. Another one-line scan can then be performed and juxtaposed to the previous scan. This process is repeated to produce a complete 2D map of the area of interest.

Mini-Wheel Encoder

The mini-Wheel Encoder is used for the positioning and dimensioning of defects in the scan axis. It can synchronize data acquisition with probe movement. It is also waterproof and compatible with Olympus standard PA wedges.

Inspecting large areas with fast C-scan acquisition is a critical feature for the aerospace industry. Scanners with suction cups are well suited to holding onto composite surfaces, so you can perform mapping with up to two precise encoded axes.

RollerFORM

The RollerFORM™ and RollerFORM XL wheel probes provide high-quality, immersion-like phased array ultrasonic testing of composite materials, such as those used in aerospace components and wind turbine blades. An affordable replacement for full 2D encoding systems, RollerFORM scanners offer a viable alternative to immersion techniques.

Mini-Wheel Encoder

The mini-Wheel Encoder is used for the positioning and dimensioning of defects in the scan axis. It can synchronize data acquisition with probe movement. It is also waterproof and compatible with Olympus standard PA wedges.

GLIDER Scanner

The GLIDER scanner is a 2-axis (X-Y) encoding scanner for the manual inspection of slightly curved or flat composite surfaces. The scanner, held by suction cups is well suited for raster scanning. Technologies: ECA, EC, UT, PA.

VersaMOUSE Scanner

The VersaMOUSE™ is a scanner designed for linear encoded scans with a phased array probe. The integrated indexing button makes it ideal for 2-D mapping applications such as CFRP flat panel and corrosion inspections. The VersaMOUSE can perform an encoded one-line scan, followed by indexing of the position in the perpendicular direction. Another one-line scan can then be performed and juxtaposed to the previous scan. This process is repeated to produce a complete 2D map of the area of interest.

Our complete line of bond testing (BT) flaw detectors provides unmatched capabilities for the location of discontinuities and other flaws in composite structures. We offer a wide range of measurement features and application-specific options for flaw detection. Some of the primary applications include the location, identification and sizing of dis-bonds, delamination, and repair (putty) areas of honeycomb composite and composite laminates in aircraft structures(wings and flaps), high-performance racing vehicles, and boat hulls.

BondMaster 600

The portable BondMaster 600 delivers a powerful combination of multimode bond testing software and highly advanced digital electronics for the nondestructive inspection of honeycomb and laminate composites and metal-to-metal bonds

35RDC

The 35RDC is a simple Go/No-Go ultrasonic gage designed to detect subsurface defects caused by impact damage on aircraft composite structures. Features a backlit LCD that displays the word GOOD if no subsurface damage is found or the word BAD when it detects subsurface damage.

BondMaster Probes

BondMaster probes include a wide variety of versatile probes such as pitch-catch, MIA (mechanical impedance analysis), and resonance probes.

Probes and transducers help you meet demanding inspection requirements with high quality probes and transducers in various frequencies, configurations, connector styles, and cable types. Olympus' experience in the design and manufacture of high quality probes and transducers helps you to meet global inspection requirements. Ask us about custom configurations.

Ultrasonic Transducers

Ultrasonic transducers are used for applications as diverse as flaw detection, thickness gaging, materials research and medical diagnostics. More than 5000 ultrasonic transducer types come in many styles, element diameters, frequencies, and connector styles.

Eddy Current Probes

Eddy current probes consist of the acquired brands of Nortec and NDT Engineering. We offer more than 10,000 standard and custom designed eddy current probes, standard references, and accessories.

Phased Array Probes

Phased array application-specific probes have a range from 0.5 MHz to 18 MHz and may come with 16, 32, 64, or 128 elements. Special probes may have up to hundreds of elements.

BondMaster Probes

BondMaster probes include a wide variety of versatile probes such as pitch-catch, MIA (mechanical impedance analysis), and resonance probes

PipeWIZARD iX

The PipeWIZARD™ iX phased array ultrasonic testing system helps pipeline companies ensure the reliable validation of girth welds during the construction process. Equally rugged and compact, the PipeWIZARD iX system is designed to facilitate both onshore and offshore pipeline inspections. A highly efficient automated ultrasonic testing (AUT) solution, this powerful multitechnology detection system reveals defects in girth welds and the heat-affected zone (HAZ) so they can be quickly analyzed and evaluated.

Bar inspection system using ultrasonic phased array, eddy current array and X-ray fluorescence spectroscopy technologies.

BIS PA: Bar Inspection System—Phased Array

The BIS PA uses phased array technology to inspect the full volume of round and square bars. The system is based on a unique “floating head” concept for a constant optimal positioning of probes; independently of the straightness variations of the bars.

RBIS: Rotating Bar Inspection System

The RBIS combines phased array and eddy current array technologies to inspect the full volume and surface of large round bars; called billet. The inspection is carried out during the rotation of the billet and the linear movement of the carriage supporting inspection head.

BIS ECA: Bar Inspection System-Eddy Current Array

The BIS ECA uses eddy current array technology to inspect the full surface of round and square bars. The system is based on a “Wear Shoes” concept for a constant optimal positioning of probes, independently of the straightness variations of the bars.

Vanta™ iX In-Line XRF Analyzer

Seamless and welded tube inspection systems using ultrasonic phased array and X-ray fluorescence spectroscopy technologies.

LSAW Tube Inspection System

Longitudinal submerged arc welded (LSAW) tubes are manufactured by bending and molding steel plate and then joining the edges using a double-sided submerged arc weld. They are commonly used in the oil and gas industry for long-distance hydrocarbon transport pipelines.

TEIS: Tube End Inspection System

The TEIS is a high-quality yet small-footprint PA or UT inspection solution that minimizes untested lengths left by other tube inspection systems. It can be integrated into fully automated systems to meet stringent volume-inspection requirements.

Vanta™ iX In-Line XRF Analyzer

The Vanta iX in-line X-ray fluorescence (XRF) analyzer gives you confidence in your products by automating material analysis and alloy identification on the manufacturing line. Built to operate 24/7 in industrial environments, the system delivers instant results for 100% inspection and continuous quality control.

RTIS: Rotating Tube Inspection System

The RTIS uses phased array technology to inspect the full body of tubes. The system is based on the “Water Wedge” concept using a membrane to maintain a permanent and stable water chamber providing a fast coupling and short untested length.

ERW In-Line: In-Line ERW Tube Inspection System

The ERW In-Line uses phased array technology to inspect weld seam and the heat-affected zone (HAZ) of electrical resistance welded (ERW) tubes. The head rotation capability allows each probe independent movement from –120 to +120 degrees for weld tracking.

ERW Off-Line: Off-Line ERW Tube Inspection System

The ERW Off-Line uses phased array technology to inspect weld seams and the heat-affected zone (HAZ) of electrical resistance welded (ERW) tubes. Using only one PA probe on each side of the weld provides wide sector coverage of the HAZ with constant amplitude.

ERW Solutions: In-Line ERW High-Temperature Inspection System

This in-line PAUT process-control system is positioned between weld cooling and annealing to inspect ERW tube seams and HAZ. Its unique self-cooling wedge and automatic alarms protect the phased array probe from temperatures up to 100 °C (212 °F).

The Wheel Inspection System’s phased array probes inspect the rim, from the tread and one face, in addition to the hub from both sides in less than one minute. The fully automated system detects the typical defects found in train wheels.

RailView Software

RailView acquisition and analysis software is PC based and offers powerful inspection features, advanced analysis tools, and fully customizable displays. This software has been designed specifically for train wheel inspection and includes features that ease the entire process. Special attention has been given to the ergonomics of the interface, providing a human-machine interface (HMI) that optimizes the wheel inspection workflow.

Evident industrial instrumentations are recognized as high performance acquisition unit and are used in the integrated inspection systems directly offered by Olympus NDT, as well as by several system integrator partners located worldwide.

FOCUS PX

The scalable FOCUS PX acquisition unit and Focus PC software incorporates the latest phased array technology for easy integration with automated and semiautomated inspection systems. The solution significantly improves SNR and inspection speeds. Available are the optional software development kits, FocusControl and FocusData.

QuickScan

The QuickScan Instruments are the data acquisition unit for industrial inspection systems. The data acquisition unit are designed for easy integration into industrial environments

The friction stir weld (FSW) inspection system incorporates unique robotics and ultrasonic phased array technology to reliably detect FSW defects at multiple orientations.

A complete turnkey inspection station, the FSW system is designed to be directly installed in the production line. Large cylindrical fuel tank welds are presented to the collaborative robot (Cobot). It positions the inspection head and the tank is rotated until the entire circumferential weld is inspected. The tank is then moved and the cycle repeats on the next weld.

Evident X-ray Fluorescence (XRF) analyzers provide elemental analysis for detection, identification, analysis, quality control, process control, regulatory compliance, and screening, for metals and alloys, mining and geology, scrap and recycling, environmental and consumer safety, education and research, and general manufacturing.

Vanta Handheld XRF Analyzers

Instantly identify materials and their chemical composition from any location using the Vanta™ handheld XRF analyzer. The Vanta series delivers fast, accurate elemental analysis and material identification using smart and cloud-connected technology. Our next-generation Vanta handheld XRF analyzers—Vanta Max and Vanta Core—combine the exceptional accuracy, speed, and durability of the Vanta series with improved ergonomics, a streamlined interface, and enhanced connectivity for greater productivity.

Vanta GX Compact and Portable XRF Analyzer

Evident offers the Vanta GX series of benchtop XRF analyzers for customers that require the power and ease-of-use of our handheld instruments in a self-contained, closed-beam instrument for precious metals analysis.  

Vanta iX Process XRF Analyzer

Our Vanta iX system enables 100% quality inspection of alloy tubes, rods and billets through material identification and elemental analysis by implementing XRF into your production line. Also available are systems for liquids analysis such as plating baths, chemical production lines, and slurries. Continuous 24/7 operation provide industrial process optimization for increased productivity and quality control.

Industrial microscopes incorporate many complex designs that aim to improve resolution and sample contrast. Evident microscopes meet a wide-variety of analysis applications, from a routine inspection to sophisticated analysis by it's wide range of microscope models strengthened by superb optical performance and a variety of accessories. The combination of digital camera and software provides streamlined workflows and flexible solutions for image acquisition, measurement and reporting as well as grain analysis, particle analysis and other material solutions. We also provide non-contact geometric measurements of electronic devices and machined parts with a high-precision measuring system.

Laser Confocal Microscopes

Our confocal laser scanning microscope offers superb image quality and accurate 3D measurement by non destructive observation method with advanced optical system. Its operation preparation is easy and no pre-process is necessary with your samples.

Digital Microscopes

DSX1000 digital microscopes enable faster failure analysis with accuracy and repeatability. Streamline your inspection workflow with fast macro-to-micro viewing, multiple observation methods at the push of a button, and a large selection of lenses that are easy to change.

Cleanliness Inspector

Evident expertise in imaging and metrology systems provides today’s manufacturers with an experienced technology leading partner to provide solutions for particle counting, sizing and classification.
Measuring particle size and distribution can directly impact the performance, life-time and reliability of many manufactured products.

Measuring Microscopes

Evident STM7 series is the measuring microscope system offering versatility, high-reliability and exceptional level of precision and durability.

Light Microscopes

Light microscopes are used for quality control applications and detailed examination of newly developed materials, electronic devices, metals, and chemicals.  Designed with modularity in mind, users can customize their system with the optical and digital imaging components required for today's discerning microscopist.

Semiconductor & Flat Panel Display Inspection Microscopes

Evident MX microscopes are developed with the concept to offer the highest efficiency for all our customers. MX microscopes ensure beneficial four levels, fast start-up, easy operation, failure analysis and expandability for users.

Stereo Microscopes

Evident SZX/SZ stereo microscopes offer clear stereoscopic view with comfortable and ergonomic operation. Extensive types of frames with variety of optical options with wide range of zoom support various applications.

Digital Cameras

Evident digital cameras are exclusively designed for microscopes. All cameras are confirmed their best digital imaging performance with Evident microscopes and software.

Image Analysis Software

Evident Image Analysis Software turns your Evident microscope into a high-performance analysis station. With an intuitive workflow, users can easily acquire images, filter, make measurements, document, and archive data.

Micro-spectrophotometer

The micro-spectrophotometer provides high speed and repeatable measurement using an optical grating and line sensor. Curved surfaces and micro spot can be measured that most spectrophotometer cannot measure.

Objective Lenses

Evident infinity-corrected objective lenses guarantee the quality, flexibility and outstanding optical performance from visible light to near infrared light.

Customized Solutions

Designed to accommodate your unique sample shape or workflow, Olympus’ customized industrial microscope solutions adapt to meet a wide range of requirements. Based on our advanced core microscope technology, our customized solutions provide you with the right microscope for your specific needs.

When you need to inspect difficult-to-access areas, Evident borescopes and visual inspection equipment are portable, intelligent solutions that meet the demands of modern industrial inspections. A host of advanced, intuitive features and a wide range of borescope, videoscope, and fiberscope lengths, diameters, and viewing options make our remote visual inspection solutions versatile for many applications. 

Industrial Videoscopes

Outstanding image quality and brightness delivered to high-resolution LCD monitors enable inspectors to see into difficult-to-access locations, such as the inside of an engine or turbine. Simple to use and offering advanced features, including HD video, 3D modeling, and video/image recording, Evident ideoscopes are leading visual inspection tools.

Industrial Fiberscopes

Fiberscopes are flexible instruments that use a fiber bundle to transmit images back to an ocular that inspectors look into. Their small diameter permits visual inspection in limited-access areas.