The G2 parts work with all Mil-Spec receiver variations. Whether building a new rifle or upgrading your current AK, the G2 trigger group should be at the top of your list. These trigger groups offer an improved trigger pull of 3-4 lbs. and eliminate the painful trigger slap common on other designs. All G2 components are heat treated to a 45-48C Rockwell hardness and manufactured with tough 4140 tool-grade carbon steel. A precision secondary machining process ensures perfect fit and function. The ?No fumble? trigger sleeve allows you to assemble the trigger group outside the rifle and drop it in as one piece. Each piece is finished in a military grade dark black oxide. This item is marked as ?TAPCO USA ? and counts as 3 U.S. Sec 922R compliant parts.