The sophisticated pulse proportional thermostat is ideal for controlling higher power ceramic heaters and for heat mats, where constant warmth and not an On/ off cycle is required. The function of this thermostat is far more sophisticated than the simpler on/off switching devices. It will very accurately control heaters and has a maximum load of 600 watts. A normal thermostat switches a heater on full power until the set temperature is achieved. It then switches the heater off completely until the temperature drops below the set value, when the cycle starts over again. The gap between the heater being switched on and then off is called hysteresis. It is between these points that the accuracy of the controller is assessed. The pulse proportional thermostat pulses electricity to the heater all the time, resulting in constant and very accurately managed warmth.