Make precise and refined imprints on leather, wood, copper, brass, aluminum and mild steel Premium Chrome Vanadium steel with differential heat treatment to achieve optimal performance and durability. 62 HRC hard stamping end produces high quality imprints and keeps the edges sharp. 42 HRC tough hammering end excels at absorbing repeated hammer strikes and maintaining durability Large, true-to-size, and precisely machined 3/16 in. letters Find the right stamp and orientation easily with engraved sizing and letter identification on the front side of each stamp Includes 9 stamps: numbers 0-9 (interchangeable stamp for numbers 6 and 9). Comes in a heavy-duty storage case