The COP 357 was a 4 shot Derringer type pistol chambered for the .357 magnum round. It was designed by Robert Hillberg, based on earlier work on the Hillberg Insurgency Weapon.

Manufactured by the now defunct COP Inc. of Torrance, California, the double action COP packed the power of 4 rounds of short-barreled .357 magnum in a package only slightly larger than the typical .25 ACP pistol, which made it a good choice for a defensive weapon or a police backup gun.

COP stood for Compact Off-Duty Police.