CVA #11 and Musket Replacement Breech Plug for CVA In-Line Rifles - AC1679 Accepts 6x1mm threaded nipple. Easily replaces existing ignition to standard #11 or musket cap Replacement breech plugs are the same reliable designs and quality that come standard with all CVA rifles This breech plug is for most all conventional in-lines and bolt-action muzzleloaders. This includes the following models: Buckhorn, Eclipse, Eclipse Hunter, Stag Horn, Magbolt 150, Firebolt, Firebolt Ultramag, Hunterbolt, Magnum Hunter.