Traceable® pocket hygrometer/dew point/thermometer has a compact design and features an electronic capacitance polymer film sensor not affected by condensation. Unit may be used in 100% humidity. To assure accuracy an individually serial-numbered Traceable® Certificate is provided from our ISO 17025 calibration laboratory accredited by A2LA. It indicates traceability to standards provided by NIST (National Institute of Standards and Technology). At the press of a button, unit recalls minimum/maximum readings. HOLD button freezes the display to record a reading. Dual display shows relative humidity with either dew point or temperature on a 3/4-inch high LCD. Rugged ABS plastic case. Supplied with a Traceable® Certificate and two AAA batteries. Replacement battery Cat. No. 1105. Electronic capacitance polymer film sensor not affected by condensation, Microprocessor sensor, Memory (Min/Max), Auto power off, Simultaneous display of relative humidity and temperature. Size: 6-1/2 x 2 x 2/3in. Relative Humidity Range: 0 to 100.0%RH. Relative Humidity Resolution: 0.1%. Relative Humidity Accuracy: ±3%RH mid-range to ±4%RH elsewhere. Dew Point Range: -20.0 to 50.0°C. Temperature Range: -4.0 to 122°F. Temperature Resolution: 0.1°. Temperature Accuracy: ±1°C. Full Range Response: 30 to 60 seconds. Display: 3/4in LCD. Sampling Rate: 1 second. Weight: 3oz. Control Company#: 4392.