The Browning Recoil Hawg ranks among the most effective muzzle brakes in the industry. It reduces muzzle jump significantly to keep the target in your scope. - Multi-port design reduces felt recoil up to 76% (depending on caliber) - Top and side ports direct gases to reduce muzzle rise - Closed bottom design helps reduce dust signature during firing - Rugged all-steel construction - Multi-caliber design that is suitable for rifles that are .30 caliber or smaller. - The Standard Recoil Hawg will fit most bull and heavy-sporter profile rifle barrels with a minimum barrel shoulder of .700 and a 5/8-24 TPI or 1/2-28 TPI threaded muzzle. The Standard Recoil Hawg fits Long Range and Varmint/Target models of X-Bolt Rifles. - The Sporter Recoil Hawg will fit most sporter contour rifle barrels with an M13 x 1.25 or M13 x .75 threaded muzzle. The Sporter Recoil Hawg fits X-Bolt Speed and Sporter models of X-Bolt rifles. - Measurements Sporter Recoil HAWG 2.2 L x .8 W