I was using this fixture with a 150 watt ceramic heater over my python's cage. Worked great in that it was able to sit on the wire screen cover directly. The two negatives I can report are:1) The strain relief were the cord goes into the socket is inadequate. Just the weight of the cord hanging over the edge of the tank is enough to pull it loos from the socket.2) After a little over two years the on/off switch no longer closes and turns off the fixture. You can wiggle the switch and it will turn back on, but after a few minutes it goes out again.So overall, for the price id expect it to last much more than two years.