Animal plastics UTH

[Bogertophis]

I also recently purchased an Animal Plastics cage (T10).
Would a reptitherm UTH work?

I don't use Animal Plastics enclosures but I use a lot of UTH- specifically FlexWatt heat tapes. Off-hand I see no reason why your reptitherm UTH wouldn't work with your new AP cage, as long as you install it correctly & it's controlled by a quality thermostat. All heating devices, such as UTH, need to be regulated, & I know from having tried a reptitherm in the past that they can get VERY hot- enough to harm your snake- if they're not adequately controlled or installed incorrectly.