When the water temperature reaches the alarm temperature and the alarm switch is closed, the alarm light turn on. When the water temperature decreases and the alarm switch is turned off, the alarm light be turned off. When the alarm temperature is reached, the response time is approximately 1 second. Working range: 0-120 degrees. Alarm temperature: 97 + -2 degrees When the water temperature is higher, the resistance value is lower. The lower the water temperature, the greater the resistance value. The water temperature sensor has 2 wires, one is connected to the water temperature meter, and the water temperature parameter is displayed. The other one is connected alarm switch, Weight: 0.12786811196 Pounds, Manufacturer: Histeaa