I have a T11 AP cage and have a 100 watt che on the hot side and a 60 watt on the cool - both regulated and it keeps the ambient temps perfect. The only trouble I've had is that now that my snake is larger I had to get bigger hides and they are on the thick side. So I ended up having to get a small UTH and Herpstat that covers the area just under that hide. He's a burrower - so to help with heat I have very little cypress mulch on that side, just enough to absorb urine / waste and put sphagnum moss (dry) in the hide. He burrows under this and its so light it does not seem to block the heat from the UTH