Tacfire's AR Pistol Build Kit Includes: (1) 9MM 4.5in Barrel, (1) 9MM Bolt Carrier Group, (1) Mil-Spec Upper Receiver, (1) Slim Free Float MLOK Hand Guard 4in, (1) Complete Lower Parts Kit, (1) Standard Receiver End Plate, (1) Mil-Spec/Commercial Castle Nut/Steel, (1) Mil-Spec Pistol Buffer Tube/Alum. w/Foam Cover, (1) Heavy Buffer, (1) Buffer Tube Spring, (1) Mil-Spec Charging Handle, (1) Dust Cover, (1) Forward Assist, (1) 1/2x36 Thread Flash Forwarder Specifications for TacFire 9mm Luger AR Build Kit: Manufacturer: TacFire Caliber: 9mm Luger Barrel Length: 4.5 in Barrel Profile: Government Barrel Twist Rate: 1-10 Threads per Inch: 1/2x36 Handguard Type: Free-Float Muzzle Device: Linear Compensator Color: Black Gun Model: AR-15 Fabric/Material: Steel Handguard Length: 4 in Handguard Style: Quad Rail Gun Rail: M-LOK Gun Type: Rifle Gun Make: AR Platform Bolt Carrier Group Included: MIL-SPEC Charging Handle Included: MIL-SPEC Weight: 8 lb Magazine Included: No Hand: Right Package Contents: TacFire 9mm Luger AR Build Kit What firearm models does the manufacturer say TacFire 9mm Luger AR Build Kit is compatible with? The manufacturer says that TacFire 9mm Luger AR Build Kit is compatible with AR-15