So You bait the trap with something, then the mouse comes along and pushes underneath the door. Once its done gorging itself it can't get out. It can't get out because it has nowhere to grab the door and lift up. Its also smooth so they can't grip well.  Flip the trap upside down to let the critter out.

But also I'M NOT GARUENTEEING THAT THE MICE WON'T GET OUT!! They could chew through if you don't check it often! If you record the trap failing to trap a mouse please put it in the comments down below, I love seeing critters out smart me! 

I hope you at least like the design, if so please download, and thanks! 

Building Instructions : Slide the door hinges through the slots or bend the main body of the trap to put the door in. Then glue or bind the roof on top in any way. ( I melted them together using a soldering tool). Then the trap is complete! 

(PS,  I did have to manually edit it with the soldering tool, but I edited it on cad and fixed the slight problems I had. That's why it looks a little rough by the hinge points.)

BELL  DESIGNS :)