Radio-Signal Remote Humidity Meter/Thermometer receives a radio signal from the remote wireless sensors. It eliminates the cable. Place the main unit at your desk or bench. Place the remote sensor module in labs, ducts, and storage facilities-even outdoors. Remote sensor sends humidity and temperature signals to the main digital display. Transmits on a frequency of 433 MHz, penetrating walls. Range is 65 to 100 feet, depending on the location or number of walls. Relative humidity range is 25 to 95% with a resolution of 1% and an accuracy of ±2% RH mid-range to ±4% RH elsewhere. Switchable thermometer range is -4 to 140°F and -20 to 60°C with a resolution of 0.1° and an accuracy of ±1°C. An individually numbered Traceable® Certificate is supplied to indicate instrument traceability to standards provided by NIST. Main unit can receive and display data from up to three different remote sensor modules. Data is transmitted every 30 seconds. Display's trend indicators show whether humidity and temperature are rising or falling. Minimum and maximum memory display allows monitoring of conditions over short or long periods including overnight or weekends. An alarm may be set in increments of 1% RH and 1°. The alarm sounds when the humidity or temperature rises above or falls below the high and low set points. Jumbo digits (1-1/8 inches high) may be read from 25 feet. Cases are high-impact, chemical-resistant ABS plastic. Furnished with a flip-open stand, wall brackets and VelcroTM to attach to any surface. Batteries operate continuously for eight months. Supplied complete with Traceable® Certificate, one main unit (4-1/4 x 4-1/2 x 3/4 inches, weight 6 oz), one remote sensor module (2-1/3 x 3-1/2 x 3/4 inches, weight 3 oz), internal humidity sensor, internal temperature sensor, two AA batteries and two AAA alkaline batteries.