Module transmits on a radio frequency of 433 MHz, penetrating walls, with a range of 100 feet. Data is transmitted every 30 seconds. Main unit can receive and display data from 3 different remote modules. Modules may be set to channel 1, 2, or 3. Display’s trend indicator shows whether temperature is rising or falling. Minimum and maximum memory display allows monitoring of conditions over short or long periods, including hours or months. Alarms may be set in 1° increments. Alarms sound when the temperature rises above or falls below the two set points. Jumbo digits (1- 1/8 inches high) may be read from 25 feet. Cases are high-impact, chemical- resistant ABS plastic. Thermometer fulfils all CDC thermometer and vaccine thermometer requirements. Total of three modules may be used with the main receiver. The splashproof remote module is supplied with an internal and external sensor. External sensor (3/16-inch diameter by 3/4-inch long) and 10-foot cable perform accurately even when both are under water. Switchable °F/°C range is –58.0 to 158.0°F and –50 to 70.0°C. Resolution is 0.1° and accuracy is ±1°C. To assure accuracy an individually serial-numbered Traceable® Certificate is provided from the manufacturer’s ISO 17025 calibration laboratory accredited by A2LA. It indicates traceability to standards provided by NIST (National Institute of Standards and Technology). Supplied with one main unit 4-1/4 x 4-1/2 x 5/8 inches, weight is 6 ounces, one remote module 2-1/3 x 3-1/2 x 3/4 inches, weight is 3 ounces, internal probe, and external probe/cable. Also supplied with a Traceable® Certificate, flip-open stand, wall bracket, Velcro® to attach to any surface, two AA and two AAA alkaline batteries (batteries operate continuously for eight months). Replacement AA battery Cat. No. 1111. Replacement AAA battery Cat. No. CON1105.