NEMO Arms Builder DC-1 Muzzle Brake .223/5.56mm 1/2x28 TPI Bead Blasted w/Black Oxide Black. Gasses exiting the bore are obstructed and redirected to mitigate rearward movement. Twin top ports direct gasses upward to stabilize the firearm for rapid return to target. The DC-1 comes pre-drilled for pinning. Specifications for NEMO Arms Builder DC-1 Muzzle Brake: Manufacturer: NEMO Arms Color: Black Finish: Bead Blasted w/ Black Oxide Gun Make: AR Platform Gun Model: AR-10 Barrel Material: 4140 Steel Package Contents: NEMO Arms Builder DC-1 Muzzle Brake What firearm models does the manufacturer say NEMO Arms Builder DC-1 Muzzle Brake is compatible with? The manufacturer says that NEMO Arms Builder DC-1 Muzzle Brake is compatible with AR-10NEMO Arms NBP-556-MB-DCS: Builder DC-1 Muzzle Brake .223/5.56mm 1/2x28 TPI Bead Blasted w/Black Oxide Black