A pack of 50 cleaning patches sized for .38 barrels. Patches are pushed through the bore on a jag or loop to wipe out powder fouling, loosened copper, solvent and dirt after brushing. Start with a few solvent-wet patches, follow with dry patches until they come out clean, and finish with a lightly oiled patch to leave a protective film that helps prevent rust. Patches are used once and thrown away, so it is worth keeping a spare pack in your cleaning kit.