Designed for use with the Lansky Controlled Angle Sharpening System. Diamond Coatings are the most abrasive type of sharpener; they’re ideal for modern, wear resistant tool steels. The medium 280 grit diamond hone is perfect for maintaining and sharpening a slightly dull edge. Medium Grit (280) Diamond Surface (Uninterrupted Diamond Coating)Brass Threaded Insert for Stainless Steel Thumb ScrewErgonomic Plastic HousingErgonomic Plastic HousingMade in the USA!N/A