The Extech TM100 is a single-input thermometer designed for Type K and J thermocouples, featuring a large backlit LCD display for easy reading in various lighting conditions. With a wide temperature range—up to 2501°F (1372°C) for Type K and 2012°F (1100°C) for Type J—it handles diverse industrial and laboratory applications. Resolution is selectable at 0.1° or 1°, providing flexibility for precise or general-purpose measurements.

Temperature readout can be displayed in °F, °C, or Kelvin (K). The Data Hold function freezes the current reading, while MAX/MIN/AVG readings include a relative time stamp to track when extremes occurred. An offset key provides a zero function for making relative measurements, useful for comparing temperature differences.

The TM100 includes an auto power off feature with disable option to conserve battery life during extended monitoring sessions. Its rugged construction and versatile feature set make it suitable for field service, HVAC, and laboratory environments requiring reliable Type K/J temperature measurement.