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TI-25M Ultrasonic Wall Thickness Gauge

Made in USA
TI-25M Wall Thickness Gauge
Click images to enlarge.
Measuring Range in Steel
0.025 - 6.00 inches
0.60 - 150.0 mm

The Check-Line TI-25M Wall Thickness Gauge accurately measures wall thickness and the extent of corrosion of all metals, ceramics, glass and most rigid plastics - from only one side!

The TI-25M can be used in a Single Thickness Reading mode or in a Scan mode , where the probe is dragged over a large measuring area. The minimum thickness reading recorded during the "scan" will be displayed.

The TI-25M probe is waterproof and can be submerged in water. The gauge is impact-resistant and environmentally sealed to provide trouble-free operation under the toughest field conditions.


  • Includes NIST Calibration Certificate
  • Resolution of 0.001 inch (0.01 mm)
  • Large, back-lit LCD display retains last reading
  • Simple operator controls virtually eliminate training
  • Special-purpose probes are offered for a variety of applications
  • Switch-selected units for inches or mm
  • For underwater surveying, probe cable lengths up to 50 feet are optionally
  • CE Certified
  • Made in the USA
  • IP 65 Rated

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Steel Test Blocks without certification
- Fabricated from 1018 Steel
- Supplied without certification
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Certified Steel Test Blocks
- Precision Machined and Finished
- Includes Wooden Storage Box
- Includes NIST-Traceable Report and Test Data
- Made from 1018 Steel
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Protective Holder for Ultrasonic Gauges
- Constructed from heavy duty Cordura Nylon
- Built-in belt loop
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Coupling Fluid
- Temp Range: 0 - 200 °F, -18 - 93 °C
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50 Foot Underwater Probe / Cable Assembly
- 50 Ft. Length, Waterproof Probe/Cable assembly with non-polarized, Dual-Lemo connectors.
ultrasonic trandsducer holder v-block
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Ultrasonic Transducer Holder

Complete Kit

The TI-25M is supplied as a complete kit with the gauge, T-102-3300 probe, 4 oz. bottle of coupling fluid, 2 AA batteries, NIST Calibration Certificate, and Operating Instruction Manual - all in a foam-fitted carrying case.
TI-25M Ultrasonic Wall Thickness Gauge Complete Kit

Measuring Limits

Minimum Radius for Convex Surfaces 0.350" (8.89 mm)
Minimum Radius for Concave Surfaces 3" (76.2 mm)
Minimum Headroom 1" (25.0 mm)
Minimum Sample Diameter 0.150" (3.8 mm)
Minimum Substrate Thickness - F na
Minimum Substrate Thickness - NFe na


Range in Steel0.025-6.00" (0.60-150.0 mm)
Resolution.001" (0.01 mm)
Display4½ - Digit, 0.5" Back-lit LCD
Velocity Range0.0492 to .3937 in/μs. 1250 to 10,000 meters/sec
Probe7.5 MHz, 0.25" Diameter (6.35 mm)
Cable4 ft. (1.2 m) waterproof cable with non-polarized, quick-disconnect connectors. Optional lengths up to 50 ft. (15 m).
Temp. LimitsAmbient: -20 to 120° F (-30 to 50° C)
Material: -0 to 200° F (-20 to 100° C
Special high temperature probes are optionally available.
Battery TypeTwo AA batteries
Battery Life200 hours
Weight7 ounces (196 g)
Size2.5 x 4.5 x 1.25"
(64 x 114 x 32 mm)
Accessories IncludedProbe/cable assembly. 4 oz. bottle of coupling fluid, NIST Calibration Certificate, 2 AA batteries, operating instructions, hard-plastic carrying case.
WarrantyGauge: 5 Years
Probes: 90 Days

Special Purpose Models

Model Description
TI-25M-H High Temperature for surfaces up to 650° F or 343° C.
Transducer is 0.5" 5.0 MHz, range .050" to 19.99"
TI-25M-107 Cast Iron / Plastics
TI-25M-HW Heavy Wall (0.040-19.999")


Buy Now

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  Item Description Price  
Ultrasonic Wall Thickness Gauge Complete Kit with T-102-3300 Probe
Ultrasonic Wall Thickness Gauge kit with High-Temp (650 F / 344 C) T-044-2000 Probe, CF4H High Temp Coupling Fluid Highly Recommended
Ultrasonic Wall Thickness Gauge kit with T-104-1000 probe for Cast Iron and Plastics
Ultrasonic Wall Thickness Gauge kit with T-104-2000 probe for Thick Walls
Ultrasonic Wall Thickness Gauge SUPPLIED WITHOUT PROBE
Protective Holder for Most TI Series Gauges, F-112-0005
Coupling Fluid - 12oz
High Temp Coupling Fluid 4oz (0 - 600 F / -18 to 316 C)
High Temp Coupling Fluid 4oz (600 - 780 F / 316 - 404 C)
V-Block Transducer Holder (For 3/16" & 1/4" Transducers only), F-000-7001
1/4" diameter, 7.5 MHz, dual element transducer (Standard Probe for TI-25M)
1/4" diameter, 5.00 MHz, dual element transducer
1/4" diameter, 2.25 MHz, dual element transducer, Side-in
1/2" diameter, 2.25 MHz dual element transducer
1/2" diameter, 5.00 MHz dual element transducer
1/2" 5.0 MHz Hi-Temp (650 F / 344 C) Transducer
1/4", 5 MHz Hi-Temp (900 F / 500 C) Transducer
4 Step Steel Test Block, 0.1 / 0.2 / 0.4 / 0.6 inch - Uncertified, supplied in plastic case
In stock
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Lead Time Varies, Please contact us for availability.