Work Sharp abrasives are formulated, designed, and made in America by industry-leading abrasives manufacturer Norton for precision sharpening of high-strength steels. The grit symmetry, spacing, and backing flexibility are all designed to produce the optimal convex edge with minimal heating or material takeoff. If you've ever used a belt sander to sharpen, you know how quickly the steel heats and how much excess material can be removed if you aren't careful. Work Sharp's abrasives are a key component of their success in the sharpening world. This Work Sharp Replacement Abrasive Kit includes (4) sharpening disks for the E2 and E2P sharpeners.