American Tactical Imports MilSport AR-15 .300 AAC Blackout 16 inch M-LOK Upper Receiver Heavy Barrel 1-8 Twist 5/8x24 A2 Flash Hider Nitride Black. 300 AAC Blackout 16 inch M-LOK Upper Receiver: Manufacturer: American Tactical Imports Caliber: .300 AAC Blackout Barrel Length: 16 in Barrel Profile: Heavy Barrel Twist Rate: 1-8 Firearms Threads Per Inch: 5/8x24 Muzzle Device: A2 Flash Hider Finish: Nitride Color: Black Gun Model: AR-15 Handguard Length: 15 in Gun Rail: M-LOK Gun Type: Rifle Gun Make: AR Platform Barrel Material: Steel Package Contents: American Tactical Imports MilSport AR-15 .300 AAC Blackout 16 inch M-LOK Upper Receiver What firearm models does the manufacturer say American Tactical Imports MilSport AR-15 .300 AAC Blackout 16 inch M-LOK Upper Receiver is compatible with? The manufacturer suggests that American Tactical Imports MilSport AR-15 .300 AAC Blackout 16 inch M-LOK Upper Receiver is compatible with AR-15American Tactical Imports ATI15MS300ML15: MilSport AR-15 .300 AAC Blackout 16 inch M-LOK Upper Receiver Heavy Barrel 1-8 Twist 5/8x24 A2 Flash Hider Nitride Black