Hand Steel Stamp Use to permanently mark tools, components, locks, and various metals. Packed in an ABS plastic case Hand Stamp Set,1/4 In,NumbersItem # 3W639Type 1/4" Number SetShank Length (In.) 3Shank Size Square 7/16"Material of Construction Alloy SteelHardness Rockwell C 57 to 59 at the Character End and 49 to 53 at the Striking EndCase Material High Impact PlasticIndication Character and ...