Thread Pitch Select: 1/2x28 TPI for .22LR .223/556 1/2x28 TPI for 9mm 1/2x36 TPI for 9mm 5/8x24 TPI for .308/300BLK/7.62 Six Ports Direct Muzzle Blast & Unburned Powder Downrange And Away From The Shooter. Made From 6061 T6 Aluminum, It Is Lightweight And Does Not Weigh Down The Front Of The Barrel. Color: Anodized Black Material: 6061 T6 Aluminum Weight：4 OZ Outer Diameter: 1.24" Length: 4.55 (Extra Long) Crush Washer Included