If you are looking for the most effective muzzle brake on the market, then look no further than the JP Enterprises Recoil Eliminator. The unique design, reminiscent of old tanks, directs the high pressure gasses from each shot to the sides and up, keeping your muzzle pointed squarely on the target. On magnum calibers, this can mean spotting your own hits, and significant reduction in recoil-induced fatigue, allowing you to shoot longer and more accurately! Exit hole is .350 for use on .308 caliber weapons, but can be enlarged to accommodate bores up to .416!