A Rubber pencil is put in a plastic case. The center of the case slides out sideways and cuts the pencil in three pieces which are removed and shown. The pieces are replaced and the center is pushed back again, and the pencil is taken out whole and undamaged.

It can be examined. Well made. Fully mechanical, simple to perform.

What's more, it can be performed with different things instead of rubber pencils.

Such as drinking straws, ropes, cigarettes, shoelace etc.