Ace Martial Arts Professional Steel Police Thumbcuffs - Thumb Cuffs;

Thumb cuffs are restraining devices. They are based on the same principle as handcuffs. They can be used as a lightweight and compact back up for the handcuffs. They are made of metal and resemble the more common wrist cuffs or handcuffs, except that thumb cuffs are designed to fit around the thumbs. They come with a set of keys for both locking and unlocking Thumb cuffs are opened and slipped around each thumb. To prevent them from slipping, make sure that they are positioned below the thumb joints. Once you close the 'cuffs around the thumbs, the slight protrusion or angle of the knuckles will prevent them from slipping off. Double locks also make picking the locks more difficult. Thumbcuffs with double locks have a lock spring which when engaged, usually using the top of the key, stops the thumb cuff from ratcheting tighter and prevents the subject from tightening them, possibly causing injury. When using thumb cuffs, remember that the chance of injury is great, and that you should be cautious not to put them on too tightly.