For In-Lines - A new nipple design that achieves the hottest ignition possible weather you are using the No. 11 cap or a musket cap. T/C's new Flame Thrower Nipple is a unique design with ignites the powder charge in a muzzleloader through both a direct vent and via side ports that work in conjunction with the inner breech plug surface to throw a "ring of fire". Both nipples fit the T/C Fire Hawk, ThunderHawk, System 1 & Black Diamond. Also other brands of in-lines that accept 1/4 x 28 thread nipples. These nipples will not work on sidelocks.