This is the same bear image and letter has been changed to C in this stained glass prairie style stained glass lamp pattern, and the top is angled in to fit into a commercially available square lamp cap that is 2 3/4 inches (the top of the pattern piece is 2.5 x 2.5 so it fits underneath the lip of the cap. The bottom dimension of the lamp is 11 inches if you construct it with the pattern at the size of this pdf file. There is a link to the cap HERE