Ambient (receiver unit) temperature range: -10 ~ 60℃ Fridge (remote sensor) temperature range: -20 ~ 65℃ Temperature accuracy: +/-1.0 Battery life: Approximately 12 months for receiver. Approximately 12 months for transmitter. Transmission frequency: 433MHZ Transmission range: 300 feet (60 meter) in open area Minimum/Maximum: Displays and records the minimum and maximum temperature Alarm thermometer : Yes , Both indoor and outdoor °F /°C: Selectable to degrees Celsius or degrees Fahrenheit Power requirement(receiver): 2XAAA LR03 batteries Power requirement(transmitter): 2XAAA LR03 batteries