Elbow trap

An arm trap is a type of restraint, usually made of rigid metal bands, which are designed to go around the elbow and hold the arm in a bent position. When locked in place, it prevents the wearer from straightening his or her arm.

An arm trap on its own does not produce much restraint. In general, it should be supplemented by a bondage mitt and/or some way to restrain the arm at the wrist.