Automatic heating: thermostat will first reach the preset temperature, then stop working until the temperature dropped a few degrees, the thermostat automatically turns on. ST series pool heaters are special used for small pool less than 5CBM, massage pool and hot spring to heat and keep warm; Meanwhile, can be a assistant for heat pump in heating.This product adopts latest constant temperature controller- -temperature sensor replaces traditional magnetic flow switch, it improves greatly of trouble free in working time, adaptability of water environment and stability. 1 x Water Heater Thermostat. This item is in the category "Home & Garden\Yard, Garden & Outdoor Living\Pools & Spas\Pool Equipment & Parts\Pool Heaters & Solar Panels". The seller is "keekoo1" and is located in this country: CN. This item can be shipped to United States, all countries in continental Asia, Canada, United Kingdom, Germany, France, Australia.