Bore Tech BTBR-06-003 Rifle Brushes Brass 6mm Bore Tech's Rifle Brass Brushes have twice the amount of phosphorous bronze (brass) bristles for doubling the scrubbing action. The core is cold-welded to the brass coupler and the bristles are filled to the end. Type: Brush Size: 6mm Quantity: 3 Pack Bristle Type: Bronze Length: 2.5" Material: Brass Thread Pattern: 8-32 Suitable For: Firearms