For intense ball-crushing play get this acrylic cock and ball crusher. This cock and ball board can apply pressure to both the cock and balls or just the balls. Simply insert the cock and balls through the back hole, then screw down the wingnuts to apply increasing pressure. If you desire you can have only your balls crushed you can simply slip your cock through the hole on the other acrylic board.

5 inches in length, 5.25 in width. Shaft hole measures 1.5 inches in diameter, ball hole measures 2 inches in diameter.  Made of clear acrylic.