What is the torture device thumb screws do?

Thumb screws are a medieval torture device used to inflict pain by crushing the thumbs or fingers of the victim. The device consists of a metal frame with screws that, when tightened, apply pressure on the digits, causing severe pain and potential injury. This method was often employed to extract confessions or punish individuals during interrogations. The psychological and physical torment inflicted by thumb screws made them a feared instrument of torture in historical contexts.