These Muzzle Loader Originals Pillow Ticking Shooting Patches feature tightly woven, traditional cotton pillow ticking that is resistant to burning.FeaturesPre-lubricated options for easier loadingStandard pillow ticking material.018 thickness Shooting Patches are designed to fill the space between round ball and barrel to provide proper seal and travel down the barrel rifling. The following general formula provides a starting point for determining the desired thickness of shooting patch: Barrel Diameter - Bullet Diameter = Patch Thickness For example, for a .50 caliber (.50") barrel with a .490" round ball, a .010" patch would be indicated. Please check with your firearm's manufacturer for recommended lead ball and patch sizes, and experiment within that recommended range to find the best performance for your gun.