The Finger-Cutting Contraption is a contraption used by Hyōdō to severe the fingers off peoples hands.
Tobaku Mokushiroku Kaiji
Hyōdō uses this contraption on Kaiji in the Tissue Box Raffle as a means of entertainment stating such a simple gamble could not bring any sensation to him.
This is also the only way for Kaiji to bet more than the money he had won from defeating Tonegawa similar to how he is forced to equip the ear drill to compensate for his lack of funds to bet.
Along with his current winnings, he is forced to bet his fingers to make up for the difference of money Hyōdō was betting with Hyōdō stating that each finger being bet has an equivalent value.
The device used to bet fingers.