This listing is: 2.5mm Lowercase Antlia Alphabet Letter Set consisting of Lowercase letters A-Z, as well as the Uppercase set consisting of letter s A-Z, ampersand and exclamation point. This measurement of the lowercase is based on the average size ascender/descender letters. Every letter is not 2.5mm. Please know, based on the actual design of the typeface that the lowercase letters i and j are larger measuring approx. 3.5mm, this is intentional as we try to stay true to the typeface. The Uppercase measuring is based on the average of the ascender/descender letters. Our Sharper Lines and high rockwell hardness rating make it good for use on stainless steel blanks. Please accept our apologies, the laser engraving on the side of the shank was mismarked at 1.5 mm. The size of the stamp impression is correct.