Stained glass pattern, squares line the top sides and bottom rows and there is a border too, around the numbers 1 2 4 and 1. I can customize this pattern for glass painting, copper foil stained glass, or leading, just ask for the numbers you want, and check out with the "customize my pattern" option on the left column menu. Versions 2 and 3 of the 1241 transom are very similar but one set of numbers is closer together than the other.