Angstadt Arms 3-Lug Devices Muzzle Adapter 9mm Luger 1.42 inch 1/2x28 TPI Black Nitride Black. Featuring a universal 3-lug interface this 3-lug muzzle device can quickly interface with any pistol caliber sound suppressor as well as the Angstadt Arms 3-Lug QD Blast Shield Made from hardened steel with a black nitride finish Does not require the use of shims. Shims can be used if specific timing is desired. Do not use a crush washer Specifications for Angstadt Arms 3-Lug 9mm Devices Muzzle Adapter: Manufacturer: Angstadt Arms Color: Black Caliber: 9mm Luger Finish: Black Nitride Fabric/Material: Hardened Steel Threads per Inch: 1/2x28 Gun Make: AR Platform Gun Model: AR-9 Length: 1.42 in Outer Diameter: 0.5 in Weight: 27 g 0.06 lb 0.9 oz Additional Features: Does not require the use of shims Included Accessories: Standard Package Contents: Angstadt Arms 3-Lug 9mm Devices Muzzle Adapter What firearm models does the manufacturer say Angstadt Arms 3-Lug 9mm Devices Muzzle Adapter is compatible with? The manufacturer says that Angstadt Arms 3-Lug 9mm Devices Muzzle Adapter is compatible with AR-9Angstadt Arms AA093LSD28: 3-Lug Devices Muzzle Adapter 9mm Luger 1.42 inch 1/2x28 TPI Black Nitride Black