STNGR AR-15 5.56 NATO 12.5in M-LOK Complete Upper w/13.5in HWKXL Handguard BCG & CH OD Green Cerakote. 5in complete upper is built around a Ballistic Advantage Modern Series government profile barrel with a carbine-length gas system for dependable cycling in a compact setup. The 12.5in length offers a solid balance of velocity and maneuverability making it well suited for defensive builds duty use or a compact range rifle. The 13.5in HWKXL handguard extends past the muzzle for a tucked suppressor-ready look while maintaining a lightweight 6061-T6 free-float platform with plenty of usable rail space. Specifications for STNGR AR-15 5.56 NATO 12.5in M-LOK Complete Upper w/13.5in HWKXL Handguard BCG & CH: Manufacturer: STNGR Caliber: 5.56x45mm NATO Barrel Length: 12.5 in Barrel Profile: Standard Gas System Length: Carbine Length Barrel Twist Rate: 1-7 Firearms Threads Per Inch: 1/2x28 Handguard Type: Free-Float Muzzle Device: Flash Hider Fabric/Material: Steel Gas Block Journal Size-Diameter: .750 in Handguard Length: 13.5 in Gun Rail: M-LOK Gun Make: AR Platform Gun Model: AR-15 Barrel Material: 4150 CMV Steel Bolt Carrier Group Included: MIL-SPEC Charging Handle Included: MIL-SPEC Features of STNGR 5.56 NATO 12.5in M-LOK Complete Upper w/13.5in HWKXL Handguard BCG & CH M-LOK slots at 3 6 and 9 o'clock with integrated QD sling points Slick side billet upper receiver with .750 low-profile gas block STNGR phosphate chrome-lined M16 BCG with C158 bolt and GI charging handle included KAK Slimline flash can directs muzzle blast forward Package Contents: STNGR 5.56 NATO 12.5in M-LOK Complete Upper w/13.5in HWKXL Handguard BCG & CH What firearm models does the manufacturer say STNGR AR-15 5.56 NATO 12.5in M-LOK Complete Upper w/13.5in HWKXL Handguard BCG & CH is compatible with? The manufacturer says that STNGR AR-15 5.56 NATO 12.5in M-LOK Complete Upper w/13.5in HWKXL Handguard BCG & CH is compatible with AR-15STNGR STNGR-CU-P-HWKXL-125-ODG: AR-15 5.56 NATO 12.5in M-LOK Complete Upper w/13.5in HWKXL Handguard BCG & CH OD Green Cerakote