A transparent base supports a large metal spike.
The magician asks to hide under one of the glasses or under a bag of paper a very sharp metal tip. The magician, now also blindfolded, holds his hand over him the glasses upside down, under one of them hides the pointed pole. When the magician feels ready squeeze the glass tightly under his hand with all your might. The test of courage is repeated once again. At the end of the act only a glass will remain intact, and after lifting it the magician will reveal the sharpened pole below it. Made with great care and precision, it works electronically with 23A and CR2016 batteries. It is completely removable for convenient use.
Supplied remote control, base transparent and sharped aluminum pole. Video instructions attached.