Arsenal Inc AR-20 Muzzle Brake 7.62x39 / 5.56x45 Caliber 14x1mm LH Thread Black Oxide One Size. 62x39mm or 5.56x45mm with 14x1mm LH threads. Stainless Steel with Black Oxide Finish. Specifications for Arsenal Inc AR-20 Muzzle Brake 7.62x39 Caliber 14x1mm: Manufacturer: Arsenal Inc Color: Black Caliber: 7.62x39mm Finish: Black Oxide Fabric/Material: Stainless Steel Threads per Inch: M14x1 LH Gun Make: Kalashnikov Barrel Material: 4140 Steel Length: 4 in Additional Features: 7.62x39 14x1mm Lh Fit: Regular Activity/Occasion: Outdoor Casual Work Duty Sports Age Group: Adults Width: 1.05 in Application: Casual Outdoor Everyday Work Seasonal/Temperature Use: All Seasons Quantity: 1 External Dimensions: 1.30 X 1.05 X 3.00 in Height: 1.3 in Dimensions: 1.30 X 1.05 X 3.00 in Internal Dimensions: 1.30 X 1.05 X 3.00 in Gender: Unisex Package Contents: Arsenal Inc AR-20 Muzzle Brake 7.62x39 Caliber 14x1mm Arsenal Inc AK-352US: AR-20 Muzzle Brake 7.62x39 / 5.56x45 Caliber 14x1mm LH Thread Black Oxide One Size