Hoppe's No. 9 Gun Universal Bore Guide soft cotton swabs These mops are perfect for removing fouling and excess Solvent 100% designed and tested for the toughest situations and environments Keeps solvents from dripping into action and prevents excessive cleaning rod contact Includes 3 interchangeable chamber tips to fit .17-.416 caliber Aluminum action collar fits .695"/.700" (17.65mm/17.78mm) Threaded brass pin locks the guide into the action in place of the bolt to allow proper cleaning from the breech