The Key to Steel (Stahlschlüssel/Stahlschluessel) includes more than 70,000 standard designations and trade names from approximately 300 steelmakers and suppliers from 25 countries.

The online version includes the ability to search for steels by designation, chemical composition, and mechanical/physical properties. Choice of language (English, German, or French)

Materials covered include structural steels, tool steels, valve steels, high temperature steels and alloys, stainless and heat-resisting steels, and more.