Original 3 Port Muscle Brake - slabbed - This brake works on anything from the 243 to the 338 Lapua. 45 to 95 gr of powder is covered pretty well by the one and only original 3 port muscle brake. Fits muzzle diameter of .685" - .990". (5/8x24 TPI) This is unused and ANIB. Bought it for a build and decided to go suppressed. $70 TYD Fee less Pay-pal, MO or Check.