About this item UltraEdge blades are constructed of carbonized steel for long edge life. Chrome finish resists rust. Fits Andis model detachable blade clippers: AG, AGC, AGP, AGRC, AGCL, AGR Plus, AGRV, DBLC, MBG, SMC Fits Oster A5 and Wahl KM Series Always oil blade before, during and after each use The Andis Pet Ultra Edge Size is hand lapped, polished, and finished for superior cutting and specially hardened for long life. The Chrome finish resists rust and helps keep blades at optimum performance and the blade fit all Andis AG, MBG, and Oster A-5 models ALL OUR BLADES ARE BRAND NEW SEALED IN PACKAGING and are very sharp! Some people have complained of dull blades - sometimes we find out its because the blades were not put in properly. Please ask a professional groomer to show you how if you don't know how. A blade "clicks" when installed properly and there is a way to hold clippers.