Perfect quality-control unit displays accurate answers for every air measurement. Self-contained, the humidity and temperature sensors are built into the case. Features a separate data hold switch so that readings may be captured and noted. Traceable to NIST General-purpose unit has a relative humidity range of 10.0 to 95.0%, with a resolution of 0.1% and an accuracy of ±1.5%. Temperature range is 32.0 to 140.0°F with a resolution of 0.1° and an accuracy of ±0.4°F. Response time is 30 seconds to 3-1/ minutes. An individual certificate is provided indicating traceability to standards provided by NIST (National Institute of Standards and Technology). Supplied with 9-volt alkaline battery for 6 months of intermittent readings or 100 continuous hours, Traceable® Certificate and handy carrying case. High-impact ABS plastic unit measures 2-3/4 x 8 x 1-1/2 inches. Weight is 8 ounces.