Shooter's Choice, Shooters Choice, Foaming Bore Cleaner, 3oz WARNING Warning WARNING WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov. Expanding foam easily cleans the bore and ensures a complete clean Simply spray in the breech to fill the bore and wait for foam to work Clean using your cleaning kit of choice Size 3oz Product Description Let expanding foam and time do the hard work in cleaning your firearm. Foaming Bore Cleaner easily cleans your bore. Simply spray in the breech end and the foam will expand to fill the bore and ensure complete product coverage. Let sit until foam breaks down and then remove using your cleaning kit of choice.