Description: Mini temperature sensor for extending the logging system TL-500 for use in outdoor & moist areas. It is ultra compact & waterproof: Included in delivery. Lithium button cell interface. Operating instructions. Radio range: 25m (50m open space). Accuracy of temperature: 0.5 degrees celcius. Temperature: -30 to +80 degrees celcius. Temperature resolution: 0.1 degrees celcius. Housing waterproof.