I have seen a variety of Simpson brush labels. With the variety, there has been some semblance of guessing the production range. There is a sticker/decal/label that seems to be a little more difficult to guess when it was made. In the image below, there is a No. 4, and (2) Vintage Major travel brushes, marked with a No. 5. The (2) Majors have different labels. The middle Major has a label/decal that matches the No. 4 on the left. These 3 might allow for identifying the label on the No. 4, which looks like a "Special". A vast variety, but alas, not mine... Early Wee Scot(not mine) Pre-1941(not mine) Nimmer Mill Somerset(not mine) An Older Somerset(not mine) 2006(not mine) 2012 (not mine) Modern Label(not mine) Most Recent Label(not mine) Are there guidelines for establishing an approximate date of manufacture based on the label? Any ideas about the No. 4 in the first image?