Since 1926, Diehl Tool Steel has been a supplier of quality tool steel and alloy steel products and services. Diehl Tool Steel was founded in 1926 in Cincinnati, Ohio to serve the needs of the metal working industry. Our focus is and has always been to serve the quick turn-around needs of the tool and die, mold shop, machine shop, and O.E.M. industries. We are a distributor of: Tool steel Alloy steel Powder metal products, including CPM (Crucible Particle Metal) Mold steel Carbon steel Stainless steel Aluminum Diehl Tool Steel maintains a large inventory of flats, rounds, drill rod and hollow-bar. Flats are available as blocks, plate, or sheet. Rounds and hollow-bar are available as long products up to 10-12', or can be furnished saw-cut to more precise specifications.