- The Keymount Muzzle Brake Is Your Gateway To Silence. When You’re Ready For Peace And Quiet Use The Keymount Brake To Quickly Attach Your Sandman-L™, Sandman-S™, Sandman-K™, Or Keymo Equipped Nomad-30 Or Primal To Your Rifle. If You’re Not Quite Ready To Turn Up The Silence, You Can Still Employ The Finest Brake On The Market And Experience A Flatter Shooting Rifle With Minimal Concussion Compared To Traditional Muzzle Brakes.