American Tactical SR-1 Stand Ready AR Buttstock Kit with Buffer Tube and Castle Nut

American Tactical Imports SR-1 STAND READY AR BUTTSTOCK KIT W/ BUFFER TUBE AND CASTLE NUT. 5 lb Package Contents: American Tactical Imports SR-1 STAND READY AR BUTTSTOCK KIT What firearm models does the manufacturer say American Tactical Imports SR-1 STAND READY AR BUTTSTOCK KIT is compatible with? The manufacturer suggests that American Tactical Imports SR-1 STAND READY AR BUTTSTOCK KIT is compatible with AR-15American Tactical Imports ATISR1STKBTCN: SR-1 STAND READY AR BUTTSTOCK KIT W/ BUFFER TUBE AND CASTLE NUT