Offering a Rockwell Hardness Rating of 62, the Oster Clipmaster Top Blade Model 83AU is a groomers best choice for standard body clipping. Each blade is made of a fine-grain carbon steel that is heat treated for a hardened surface and better durability. The Cryogen-X process takes the blades down to deep freeze levels making for a harder, sharper blade which extends product life. Finally, each Top Blade is hand lapped for a smooth cut finish that provides the quality performance and style clients expect.