What makes this product unique is that it does not require any modification to the receiver of the gun. It is built in to the rear of the bolt and does not affect the normal function of the gun in the unlocked position. A spring-loaded plunger insures that the bolt lock device does not rotate and guarantees flawless reliability. When maximum suppression is required you can effortlessly turn the device counter clockwise into the locked position and the gun will not cycle. Once you are ready to chamber an additional cartridge, simply rotate it to its original position and you are ready to continue in normal semi-automatic operation.