SAP Gloves or Hard Knuckle Gloves are a self defense weapon used in hand-to-hand combat. They consist of a pair of ordinary looking gloves usually made of leather or a synthetic material, with powdered lead or steel sewn into a special pouch covering the knuckles, and often the backs of the fingers and the back of the hand. In some designs, this distinctive feature is obvious, while in others it is almost completely indistinguishable from an ordinary glove, allowing the gloves to be worn in plain sight without suspicion.
The purpose of these gloves in combat is both offensive and defensive. Offensively, the weight of the metal powder adds mass and, by doing so, also adds kinetic energy to punches, back-hands, and other hand strikes.
However, the primary aim of the gloves is to protect the user from injury. Normally, punches with an unprotected hand to an opponent's head/face will painfully injure the hand in the process, and strikes to the mouth can often result in severe lacerations and possible infection from the opponent's teeth.
They are primarily used by security guards and by bouncers and other security professionals where physical combat is expected. Great to wear while on a motorcycle in case of an accident.
In some jurisdictions, weighted-knuckle gloves are prohibited or restricted as dangerous weapons.