Non-mercuric, non-corrosive, and darned reliable, CCI Muzzleloader Percussion Caps makes muzzleloading much more enjoyable. Assembled in ribbed copper cups just like the originals, these caps deliver clean burning, reliable ignition. Use #11 for standard setups. #11M provide a bit more power to light off replica black powders. #10 caps work in revolvers with smaller nipples. Caps match standard nipple sizes. Reliable percussion caps for muzzleloaders Reliable, clean-burning ignition Match standard nipple sizes Available in #11, #11M, and #10 sizes Modern non-corrosive, non-mercuric priming mix Ribbed copper cups