Hoppe's Rifle Cleaning Brushes - Use a caliber specific Hoppe's Chamber Brush and your favorite Hoppe's gun bore cleaner to clear residue and fouling from the chamber of AR-15 and AR-10 rifles after a day at the range. The dual diameters of the chamber brush are designed specifically to fit into the chamber of AR rifles and remove hard to clean powder, lead, and metal fouling easily. Available in .223/5.56mm or .308/7.62mm Available in a single brush pack or a pack of three brushes Bore brush section is phosphorus bronze and chamber section is steel 8-32 threading Fits standard cleaning rods