PROFESSIONAL GRADE QUICK CHANGE DISCS ROLOC COMPATIBLE QUICK CHANGE DISCS TYPE R & TYPE S. LONG LASTING DESIGN Zirconia, Aluminum Oxide, and Ceramic grain. Available in Surface Conditioning Discs and Flap Discs. FLAP DISCS QUICK CHANGE CERAMIC FLAP DISCS TYPE R & S QUICK CHANGE ZIRCONIA FLAP DISCS TYPE R & S