Matching Serial Numbers? Last week, I posted a c.1918 Waltham Duo-Tone P.S. Bartlett that featured unusual gilt-damaskeened upper plates paired with a nickel pillar plate and balance cock. This spurred a discussion questioning whether the serial numbers on the individual parts would match. While evidence supports that these movements were distributed from the factory with this unusual duo-tone combination, it was unclear whether these were intentionally designed (with matching serial numbers) or haphazardly combined at the factory from existing mismatched inventory to create a marketable movement (with mismatched serial numbers). What do you think? Will the serial numbers match on all serialized parts or not…? Comment below or on our Facebook Post.