3/32? (2.35 mm) shanks Bristle Brushes are used to clean and prepare surfaces for buffing and polishing. Bristle Brushes are used to clean and prepare flat, curved, and uneven surfaces for buffing and polishing and to polish with polishing compounds. They are made with natural bristles–chunking for stiff, horsehair for firm, and goat hair for soft bristles. Steel rings hold and evenly distribute bristles. 25,000 Maximum RPMs. Bristle Brushes are used to clean and prepare surfaces for buffing and polishing. Bristle Brushes are used to clean and prepare flat, curved, and uneven surfaces for buffing and polishing and to polish with polishing compounds. They are made with natural bristles–chunking for stiff, horsehair for firm, and goat hair for soft bristles. 3/32? (2.35 mm) shanks. Steel rings hold and evenly distribute bristles. 25,000 Maximum RPMs. Measurements are in Millimeters Part No. – Bristle Type – Size – Pack Quantity Wheel-Shape Head Diameter A-MB22-12 – White Goat – 22 mm – 12-pk A-MB21-12 – White Horse – 14.2 mm – 12-pk A-MB23-12 – White Horse – 19 mm – 12 pk A-MB24-12 – Black Chunking – 22 mm – 12-pk A-MB25-12 – Gray Goat – 22 mm – 12-pk A-MB26-12 – Brown/White Mix – 22 mm – 12-pk Star-Shape Head Diameter A-SB20-12 – White Goat – 22 mm – 12-pk A-SB21-12 – White Horse – 22 mm – 12-pk A-SB23-12 – White Chunking – 22 mm – 12-pk Star Anise-Shape Head Diameter A-AS30-12 – White Goat – 22 mm – 12-pk A-AS31-12 – White Horse – 22 mm – 12-pk A-AS33-12 – White Chunking – 22 mm – 12-pk End Brushes Diameter x Length A-MB35-24 – White Horse – 4.8 x 9.5 mm – 24-pk A-MB33-24 – Black Chunking – 4.8 x 9.5 mm – 24-pk Cup Brushes Diameter x Length A-MB11-12 – Gray Goat – 12 x 9.5 mm – 2-pk A-MB12-12 – White Horse – 2 x 9.5 mm – 12-pk A-MB13-12 – Black Chunking – 12 x 9.5 mm – 12-pk