Borrowed from another site... The 16 countable parts of an AK rifle. No more than 10 of these parts may be imported. (1) Receiver* (2) Barrel (3) Trunnion (4) Muzzle attachments(flash hiders, brakes, barrel extensions, barrel nuts)* (5) Bolt (6) Bolt carrier (7) Gas piston* (8) Trigger* (9) Hammer* (10) Disconnecter* (11) Buttstock* (12) Pistol grip* (13) Forearm handguards* (14) Magazine body (15) Follower (16) Floorplate The starred parts are the most commonly available U.S. manufactured parts. On a typical stamped receiver rifle you need to replace 5 parts with no muzzle attachment and 6 parts with a muzzle attachment. On a typical milled receiver rifle you need to replace 4 parts with no muzzle attachment and 5 parts with a muzzle attachment, because there isn't a barrel trunion, it is part of the receiver. When building an AK pistol, these regulations do not apply. You can not have a stock or forward pistol grip on a pistol.