T/C Speed Breech 3 Breech Plug This breech plug fits the Thompson Center Arms Pro Hunter FX Muzzle Loader and some T/C WeatherShield muzzleloader barrels. Breech plugs can get crudded up and near impossible to clean after awhile... It's easier to just get a new one! Or, order a spare in case you lose your original breech plug. Includes a new O-ring. See accessories at our TC Muzzle Loader Accessories page.