The PRYOR IMPRESSION PI10025 set includes 10 punches, 1 off each character 0-9 with 3/32 inches size characters (2.5 millimeters). each punch in the set is hardened throughout to avoid weak spots and then tempered at the striking end to give maximum safety in use and produce the most reliable mark possible on material up to maximum hardness of 37 Rockwell C. Each punch is beveled to the character face allowing for accurate positioning and the Pryor wider style of engraved character can accommodate material debris and avoid cracks in the character thus offering durability and long life. Each punch is supplied with a Blue treated finish and brushed with oil to resist rust. An identifier is clearly and consistently marked in the same place on the blank for quick character orientation and speed of application. Punches are supplied in a strong durable red plastic box with separating compartments for ease of character selection.