Having a sharp chainsaw blade improves its performance and safety. Dremel's high-quality Chainsaw Sharpening stones can quickly and easily keep your chains, gardening tools, and other tools blades sharp and ready for use. The 455 (Pink) Chainsaw Sharpening Stone is made of aluminum oxide and features a 7/32 In. (5.6 mm) diameter. The Sharpening Stone can be used for 7/32 In. pitch chain sizes and use with the Dremel A679 Chainsaw Sharpener attachment is recommended.