HHIP 3/8" Optical Punch Set Punch size is 3/8". Overall length range is less than 4". Made of tempered steel. Overall length is 2-3/4". Body diameter is 3/8". Pin length is 2" Allows you to punch layout points within .002" of location easily. Even the inexperienced can punch accurate holes every time with this set. It is indispensable when doing critical layout work. Just look down the magnifying lens and align the cross hairs with the mark on your work piece. Replace the magnifier with the supplied punch and give it a tap. The set includes a bull's eye and cross hair lens, a 150 degree and a 60 degree center punch, and a fitted case.