After many problems with heating my tank, i found this beast. Every reptile specific infra red bulb was a max of 100w. this wasn't cutting it for my 55 gallon tank. This thing can operate at about 1/3 power and still crank out plenty heat. however, MUST BE USED IN CONJUNCTION W/ A DIMMER!!!! This thing does not produce much visible light, in the form of red light which leos cant see, but it produces tons of infrared heat rays which are the main benefits of all red night bulbs. This thing is quite large like some of the larger mercury vapor bulbs, so i recommend the largest diameter deep dome lamp you can find but if you want, it has its own reflector so you could use a cage lamp. VERY POWERFUL!!! USE W/ CARE & ONLY FOR LARGE ENCLOSURES!!! I found this light at Walmart with the rest of the every day light bulbs for $8.47. It also has a life of 5,000 hours as compared to my 100w reptile infrared bulb that advertises only 3,000 hours. You will also probably be using it under 1/2 power so it should last much longer than 5,000 hours.