Review on REPTI ZOO Reptile Tank Heater: Upgraded Waterproof Heat Mat for 1-40 Gallon Terrariums, Ideal for Snake, Lizard, Bearded Dragon, Hermit Crab, Leopard Gecko by Rebecca Johnson

This is a flat UTX for a reptile and it works pretty well. You install this type on the outside of your tank. The water resistance is good but not reliable enough to put it in. When plugged in it heats up and if you can create a mini vacuum under your aquarium, which is not difficult with any standard aquarium, the heat will rise and hit your reptile. This particular product looks pretty solid, has good instructions, but it doesn't come with a manual thermostat, instead it comes with a mysterious chip that supposedly controls the temperature. Unfortunately, this is almost impossible to verify. In most cases, a slide or rotary thermostat is actually a disposable item.