Having a sharp chainsaw blade improves its performance and safety. Dremel's high-quality Chainsaw Sharpening stones can quickly and easily keep your chainsaw, gardening tools, and other tools blades sharp and ready for use. The 453 (Blue) Chainsaw Sharpening Stone is made of steel and features a 5/32 In. (4.0 mm) diameter. The Sharpening Stone can be used for ¼ In. and 3/8 In. pitch low profile chain sizes and use with the Dremel A679 Chainsaw Sharpener attachment is recommended.