Manufactured from high quality steel and induction hardened for durability and extended life , Stamping end hardened to 58-62 HRC – striking end hardened to 38-43 HRC to prevent splintering , Striking ends are beveled to prevent breakage and to increase operator safety , Sets contain: Numbers: "0-Inch , "9-Inch (6 and 9 are interchangeable) , Letters: "A" , "Z" and " and " (ampersand)