Oster Replacement Blade for Classic 76, Octane and More - 0000 SteelOster Detachable Replacement Blade for Classic 76, Octane and More 0000 Steel Oster Professional blades are produced from the finest high carbon steel and handcrafted to our rigorous standards, providing unparalleled precision and performance. Furthermore, our U. S. made blades are hardened to RC62 66 (Rockwell Scale C) in house prior to receiving a cryogenic treatment which further enhances the hardening process. The blade cutting surfaces are then