Casket (with a little trick)

It's a very small casket just 50x40mm
Cool thing is, that is has a left hand thread. If it´s closed, people usually try to open it by rotating like you would do for a right hand thread...
So they will just close it more. It fantastic. I showed it to some people and not everybody was able to open it..
Funny little thing. And very practicable.
have fun printing it.