OK, here's another entry on this controversial subject. I picked up this single ring in a Times Square box for a steal, hoping that it would turn out to be an early 1906 4xx,xxx serial number. It arrived this week, and of course my first action was to pull out the shaft and check the serial number. Much to my astonishment, it appears to read 280,226 . Got out the magnifying glass and could not detect even a hint of a letter before the number. The blade plate has no markings, and the tube has the 1904 pat. stamping. After perusing quite a few threads on the subject, i could only find mention of one other single ring with a 2xx,xxx number (288,248), which was mentioned here: http://badgerandblade.com/vb/showthread.php/157667-early-Single-Ring-from-1905?highlight=lowest+number+single+ring Of course, the single and double ring shafts are identical, so there is no way to really tell if one was switched at some point in the past 105 years. I'm still happy to have a great old case and razor for $20, but disappointed that I may never know for sure if it is a prototype, test market razor, or just a mis-matched set.