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381b Combination Non-Contact / Contact Thermometer. Measure hard-to-reach, sensitive, or large
moving target areas.

  • 381b Non-Contact IR ThermometerRepeatable, 0.1° resolution readings ensure tests are consistently correct.
  • Circle laser sighting; The circle laser approximates the measurement area.
  • Temperature compensated for accurate readings.
  • Don’t have to hit a hold button holds last reading automatically.
  • Easy-to-use one button operation you can’t lock up chip by pressing multiple buttons at one time and therefore don’t have to disconnect the battery to reboot the chip.
  • °C and °F selectable
  • 9 to 1 D:S

Product Documentationpdf-icon1

Click below to view or download product documentation PDFs:

381b Product Sheet

381b Manual

$84.95 USA Suggested List Price
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Frequently Asked Questions

  1. What does “distance to spot ratio” mean?
    The laser spot needs to be showing inside the target area. An 8:1 “distance to spot ratio” means you are measuring a 1” diameter area at a distance of 8”.
  2. How far can I measure?
    Distance is unlimited. The size of the target area sets the limit on distance for accurate measurements. Example: If the area you wish to measure is 1 foot in diameter, then you will need to be within 8 feet to record an accurate temperature.
  3. What is the smallest target I can read?
    Approximately one-half inch in diameter.
  4. What is emmisivity?
    This is a ratio of an object’s infrared emission compared to a theoretical black body considered 1. Emissivity is always less than 1. Adjustable emissivity allows your non-contact thermometer to be adjusted to the surface you are checking to make readings more accurate.

Distance to Spot Ratio: 9 : 1
Temperature Non-contact: -4° to 572°F (-20° to 300°C)
Range Contact:* -148° to 2192°F (-100° to 1200°C)
IR Accuracy: @ 23°C ± 5°F (3°C) below 32°F (0°C) and 0.95 emissivity ± 2% of rdg or ± 3.5°F (2°C) whichever is greater at >32°F (0°C)
Contact Accuracy: +(0.5% of reading + 3.5°F (2°C)
Emissivity: 0.95
Laser Sighting: Output <1mW, Wavelength 645-660nm, Class II Laser
°F or °C: Selectable (slide switch in handle)
Contact or Non-contact: Selectable: (slide switch in handle)
Display Hold: Yes
Response Time: 500 millisecond
Spectral Response: 7 – 14 um
Operating Temperature: 32° to 120°F (0° to 50°C)
Battery Type: 9 Volt

*Overall K-Type range shown. Actual range is dependent on the temperature range of the probe selected

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  • Compressor heads
  • Vents
  • Hot and cold areas in insulation
  • Leaks around cooler or freezer doors
  • Leaks around windows
  • Steam traps
  • Registers


  • Cables
  • Circuit breakers
  • Connections
  • Machinery
  • Motors
  • Transformers


  • Grill & surface temperatures
  • Holding cabinets
  • Serving temperatures
  • Storage temperatures

Distance to Spot Ratios (D:S) for TPI IR (Non-contact) Thermometers:

Models 375 / 376 / 377 (11.5:1):








Models 380 / 381 / 383 / 384 (9:1):


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