Widely Used: Designed for use in the swimming pool heated pool wood fired tubs spa thermometer monitor the temperatures in a koi pond monitor the temperature in outside hot tub from inside the house.Multi-function: Snooze function Alarm; Adjustable calendar; Radio controlled time. Measure Range: Outdoor temperature range: -40F~140F-40C ~ 60C; Indoor temperature range: 32F~122F0C~50CEasy to Use: You can read the water temperature from both indoors and outdoors. Check outdoor temperature of the swimming pool water even when you in the living room.Material: Made of ABS has high stability and good waterproof performance. Solar power with Digital LCD Display. Easy to see the data.Note: 1. Please use a good alkaline battery do not use rechargeable battery. 2. Please install outdoor transmitter (sensor) power supply first and then install indoor receiver (display) power supply.