The HabiStat Mat Stat is an on/off thermostat that used for controlling the temperature of heat mats and other low powered heaters up to a maximum load of 300 watts.
When switched on the power indicator will shine and when the heat source is switched on the heat indicator will shine.
Please note this thermostat is not suitable for controlling light bulbs. The constant turning on and off of the light bulb would not only distress your animals but would cause frequent failure of the lamps. This, in turn, is very likely to make your thermostat fail. For light emmiting heat sources use a HabiStat dimming thermostat.