Spike's Tactical Lower Receiver Parts Kit Standard, 223 Rem/556NATO, Rounded Hammerand Hammer Spring, Trigger and Trigger Spring, Disconnector and Disconnector Spring, Safety Selector, Detent, Spring, Bolt Catch, Roll Pin, Plunger, Magazine Catch, Trigger Guard, A2 Pistol Grip. Black Finish SLPK101 The Spike's Tactical LPK exceeds Military Specifications by a long shot while also offering a much better fit and finish. Proudly 100% made right here in the USA.