Ceramic Replacement Cutter Fits Most Andis Oster Wahl AG/A5 Clipper Blades LONG LASTING: Made from a high-tech ceramic material to stay sharper longer. Heat resistant for a cooler and more comfortable cutting. Rockwell Hardness rating of 78. EASY INSTALLATION: This replaces the small moving cutter blade. Can also be used to upgrade steel blades to ceramic blades. Simply replace the steel cutter of a steel blade with a ceramic cutter. SAVES YOU MONEY: Replacing just the cutter part of the blade is much less expensive than replacing the entire blade. Save your money and buy a high quality and durable ceramic cutter blade NOW