On the left is the standard CD 1085, which is unembossed. On the right is the S.B.T.& T.CO. spool. The price guide notes {CD variant; wire groove is smaller and higher up}. It is also slightly taller, and slightly smaller in diameter each by about 3/32". It also has a rounded top that is not plunged in and has no recessed indentation.

The spool has a little damage, which is why it is not perfectly straight at the bottom left, and has a little staining in a fracture, thus the discoloration in the photo.