The Muzzleloader Nylon Bore Brushes are made to fit all .50 caliber rifle and pistol barrels. The 3 pack of bore brushes are made from non-sparking nylon for quick and easy cleaning of your bore. The .50 caliber nylon bore brushes thread directly onto your ramrod or range rod for easy use. The Muzzle-Loaders Nylon Bore Brushes are all you need to make cleaning your muzzleloader a breeze.