The VG6 Epsilon AK carries many of the same characteristics as the Gamma line of muzzle brakes with a few exceptions. Extended flash hiding prongs allow uninhibited view from flash through optics or sights. The difference in porting is noticed on the underside of the device where it has 6 valve holes to allow the fastest gasses reaching the second chamber to exit. This creates very soft low energy recoil that allows for absolute control. Material: 17-4phA(R) Heat Treated Stainless Steel Finish: BLACKNITRIDE? Surface Hardness: 68RC Caliber: 7.62 x 39mm Only Thread: 14A-1.0 LH Weight: 2.24oz Indexing pin slot for standard AK47 muzzle device Mfg: Aero Precision