Manticore Arms Nightbrake Compensator For AR-15. A total of 18 ports distributed on the up half of the muzzle device help stabilize and reduce exiting gas pressure while the lack of ports on the underside prevent dust signature. The Nightbrake is threaded 1/2 x 28 tpi and will clear any projectile up to 0.311 caliber or 7.62 mm and is marked "MA" to denote it as a made in specialized factories 922r compliant part. A crush washer is included with the muzzle device. Features/Specifications: Material: 8620 steel with Rockwell 50C heat treat Finish: Black Oxide Weight: 2.0 ounces Length: 1.875 inches 100percent designed and manfuactured in the USA Specifications for Manticore Arms Nightbrake 1/2x28 Compensator For AR-15: Manufacturer: Manticore Arms Color: Black Caliber: 7.62x51mm NATO Fabric/Material: Steel Threads per Inch: 1/2x28 Gun Model: AR-15 Length: 1.875 in Weight: 2 oz Features of Manticore Arms Nightbrake 1/2x28 Compensator For AR-15 Material: 8620 steel with Rockwell 50C heat treat Finish: Black Oxide Weight: 2.0 ounces Length: 1.875 inches 100percent designed and manfuactured in the USA Package Contents: Manticore Arms Nightbrake 1/2x28 Compensator For AR-15 The Manticore Arms Manticore Nightbrake 1/2x28 Compensator For Ar-15 is a quality addition to the Manticore Arms lineup. For more great deals on Muzzle Brakes & Compensators by Manticore Arms please browse our Manticore Arms Gun Parts page. What firearm models does the manufacturer say Manticore Arms Nightbrake 1/2x28 Compensator For AR-15 is compatible with? The manufacturer suggests that Manticore Arms Nightbrake 1/2x28 Compensator For AR-15 is compatible with AR-15Manticore Arms Nightbrake 1/2x28 Compensator For AR-15