shoe box
drill 1 1/4 inch hole in top
half fill with vermiculite
wet it to desired wetness/dampness
find a shelf above the refridgerator, NOT ON the fridge...the door opening will shake the box
fridges put off heat...
works fine....for most colubridae

....my cave rats are in box ,setting on a shelf in a rack in the snake room, stays around 80 on that rack...not sure the temp is correct...but I'll find out....if you have a snake room....you have heat source...

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........JY