^Agreed. When I plug my UTH in directly to the wall and test the temps a few hours later, it's way too hot. The rheostats are a must have, IMO, and a probe temp. guage should also be used. I also use a lot of aspen over the heater so the snakes can burrow as deep as they want. Lights aren't the best for snakes since it's the belly heat that is required to help them digest.