Thank you! The T3 is 36x24x12 and it says the Flexwatt belly heat I can add on is 11".. I feel like it should be slightly bigger but I haven't used an insulated cage like this before, so it'll probably do better than I think. I appreciate the + for sliding doors. I figured it would be nice for feeding. I don't want to drop $$$ on a cage and then be unhappy with something that I chose..after waiting like 10 weeks to get it built! X.X