Features: Indoor humidity (%RH) Wireless outdoor and indoor temperature (°F or °C) Records min. and max. humidity Records min. and max. temperature Forecast icons based on changing barometric pressure Barometric pressure tendency arrow Radio Controlled Time and Date with Manual Override 12 or 24-hour time display Perpetual calendar Time alarm Can receive up to 3 sensors (optional) LED backlight Wall hanging or free standing Included transmitter WH-3 Synchronized instant reception Low power consumption (over 2 years of battery life for remote sensor) Specifications: Indoor humidity range: 20% to 99% Wireless outdoor temperature range: -40°F to 149°F Indoor temperature range: 14°F to 140°F Temperature accuracy 2.0°F Transmission range: up to 300 ft Transmission frequency: 433MHz Power requirements: Receiver: 2 x AA alkaline batteries (not included) Wireless sensor: 2 x AAA alkaline batteries (not included) Dimensions (LxWxH): Receiver: 5.5 x 3.25 x 1.0 in Sensor: 3.5 x 2.75 x 1.25 in