Comstock Armory Compact Facemount Plan-B Muzzle Brake, 1/2x28, 9mm, Black Nitride The Comstock Armory MBC-12-9-FM is a compact facemount muzzle brake combining 1/2x28 barrel threads with a Plan-B suppressor-mount interface. Its 9mm configuration, 17-4 PH stainless steel construction and black nitride finish identify this exact version. This specialized facemount design is intended for a barrel that lacks a suitable mounting shoulder. It seats against the muzzle face and is not intended for a conventional shouldered barrel such as a standard AR-15 barrel. Matching the thread pitch alone does not establish fit. Shop the Comstock Armory MBC-12-9-FM at BattleHawk Armory for your compatible 1/2x28 setup. Recoil Reduction and Blast-Baffle Protection The brake geometry helps reduce recoil and provides a sacrificial surface ahead of a compatible suppressor's blast baffle. The steel body combines those functions with the mounting interface, making the device useful when recoil management and suppressor compatibility are both priorities. The rotationally symmetric body does not require timing shims. Its black nitride treatment gives the stainless steel a durable, dark finish, while the wrench flats provide a dedicated tool interface. Compatibility and Configuration The suppressor-side interface fits compatible 0.900-24 Plan-B adapters, including Comstock LPA, Q Plan-B and Rearden Atlas. Barrel threading, bore clearance and the suppressor's internal space must all suit the intended configuration. The muzzle device does not establish the caliber rating of the suppressor. The facemount body overlaps the barrel by 0.50 inch. Some barrel geometries can leave threads visible at its rear. The complete device is 1.6 inches long and weighs 2.0 ounces. Select this version specifically for its face-seating geometry. Product Specifications Manufacturer: Comstock Armory Model / Manufacturer SKU: MBC-12-9-FM UPC: 850069580193 Product type: Compact Facemount Muzzle Brake Material: 17-4 PH stainless steel Finish: Black nitride Weight: 2.0 oz Barrel threads: 1/2x28 Mounting system: Plan-B pattern; complete-system fitment required Bore compatibility: Up to 9mm Overall length: 1.6 inches Mounting geometry: Facemount for barrels without a suitable shoulder; 0.50-inch barrel overlap Frequently Asked Questions Is a suppressor included? No. This product is the muzzle device. A compatible suppressor and suppressor-side adapter are separate components. Can I use this on a standard shouldered barrel? This facemount version is intended for a barrel without a suitable shoulder. Choose the correct mounting geometry as well as the correct thread pitch and bore. Choose the Comstock Armory MBC-12-9-FM at BattleHawk Armory for a correctly matched compact facemount muzzle brake and Plan-B mounting interface.