Durable grade O1 (oil hardened) tool steel rods resist wear and abrasion. Although not as strong as grade A2 rods, they can be hardened at low temperatures and maintain their stability and shape when heat treated. They are free of decarburization and are often manufactured into knives, punches, bushings, dies, and gauges.

Grade A2 (air hardened) tool steel rods and discs are easy to cut and shape with machine tools. They resist wear and maintain their shape and stability under heat treatment and compression after tempering and hardening. With no surface imperfections or decarburization, they are often manufactured into cold-forming tools, dies, punches, blades, and hammers.

Grade D2 (air hardened) tool steel rods and discs contain carbon and chromium to withstand wear, abrasion, and corrosion. They resist cracking, chipping, and maintain their stability and shape when heat treated. These rods are free of decarburization and are often manufactured into knives, punches, bushings, dies, rolls, tools, and gauges.

Grade M2 (air or oil hardened) tool steel resists decarburization and withstands exposure to elevated temperatures produced by high machining speeds. These rods contain tungsten and molybdenum for added wear resistance and are often manufactured into drill bits, boring tools, punches, milling cutters, reamers, saws, and knives. Grade M2 is the most widely used tool steel for high-speed applications.