The Zoo Med Creatures CreatureTherm Heater is an easy-to-use under-tank heater for glass terrariums. This energy-efficient heater only uses 4 watts, making it ideal for maintaining a healthy temperature in your arachnid, insect, or invertebrate's habitat. Includes full instructions for set-up and use.4 watt energy-efficient heaterDesigned for use with glass terrariumsHelps maintain proper temperaturesComplete instructions includedSpecifications:4 watts120VAC, 60 HzUL listed