Lower receiver design based on the Anderson Firearms Hellfire. See included PDF if unsure how to print or assemble. Pic rail buffer adapter is printed rail side down, supports touching buildplate Print 1 extra "Main Fastener Bolt" on top of the normal 4 for a total of 5. 1 extra is required for handguard clamp **This lower does not have a bolt catch or front takedown pin provision as it was designed to be used with the included handguard**