Amprobe TH-3 Relative Humidity Temperature Meter Relative humidity (RH) and temperature meter is used for HVAC, indoor air quality, and environmental applications Dual-scale thermometer measures air temperature readings in F and C Capacitive humidity sensor ranges from 0 to 100 percent relative humidity (RH) Data hold for recording data, and minimum, maximum, and relative temperature readings Extended probe with protective cover reaches inside ducts and other hard to reach areas Operating Conditions: 0 C to 40 C Storage Conditions: -10 C to 60 C; &lt;70 % RH Altitude: Up to 2000 meters Sample rate: 2.5 times per second Battery Life: 85-hours continuous (with alkaline battery)