3M™ Sof-Lex™ finishing and polishing discs, 1/2" diameter, medium, 8690M. Features: - Flexible polishing discs with aluminum oxide coating. - Pop-on discs conform to the contours of the teeth for easy finishing and polishing. - Discs can be easily changed due to the patented Pop-On™ Mandrel System. - Unique, flexible shape easily adapts to irregular, convex and concave tooth surfaces. - Effective at reaching anterior and posterior restorations.