There is a double zero (00) size mark opposite the handle. Lodge made 00 (the smallest), 0, 1, and 2 hammered skillets. The 00 is the most frequent one found. The other markings are pattern marks. Since these skillets are so small, you can fit a bunch of them on one pattern. The markings indicate pattern position. In case a defect appears, they know where on the pattern the skillet came from by looking at the mark.