Features Use to permanently mark tools, components, locks, and various metals. Character and size are indicated on the thumb side. Impressions are Gothic letters. For handheld hammer-struck applications. Letter sets contain 27 stamps: A through Z and an ampersand S55C Steel Plate High-carbon steel construction for professional results and durability. Capable of imprinting metals up to a hardness of 58 to 60 Rockwell C. Shank Length / 2-3/8Inch Shank Size Square / 1/4 inch Hardness / 58 to 62HRC at the Engraving End and 38 to 46HRC at the Striking End Case Material / Plastic Includes / 27 Pieces A Thru Z and an Ampersand