Use the compact professional humidity module to carry out wireless humidity/temperature measurement with the appropriate radio handle and measuring instrument (both available to order separately). ● For wireless humidity and temperature measurements● Can be attached to different Testo radio handles (available to order separately)● High precision in humidity measurement● Temperature measuring range: -20 to +70 °CThe humidity module can be attached to various Testo radio handles. It enables a high level of accuracy thanks to the precise humidity sensor.Wireless handle (0554 0189) and wireless module (0554 0188) are required to use a radio probe, and these can be ordered optionally. Specification Temperature - NTCMeasuring range : -4.0° to 158.0 °F / -20 to +70 °CAccuracy : ±0.5 °F / ±0.3 °CResolution : 32.2 °F / 0.1 °CHumidity - CapacitiveMeasuring range :0 to +100 %rHAccuracy : ±2 %rH (+2 to +98 %rH)Resolution : 0.1 %rH