the simplest box. i just used scrap 1/2 plywood for the door, top, bottom. for the sides i used 1/3s. the bolt is like 9/16ths i just drilled a hole thru the side and door and screwed that bolt and washer into it. tightening it makes the dooor harder to move. it can be any size you want. some of mine i put an eye hook on top to pick it up with a hook. there are much nicer and more complicated shift boxes out there, like the ones where the top slides back to reveal a lexan cover to allow you to see inside. mines just screwed together. the snakes have never pooped in their shift boxes. i think this one is 10 by 18 or so