EclipseRedRing
I smell like a Christmas pudding
The Cavalier, Somerset, and Algonquin Gillette razors, and possibly others, have such engraving and are regular models as I understand it. They are rare but they are not custom as far as I know.The regular Gillettes don't have such inravings. I'm no expert, but this was definitely a custom made razor for someone. I've seen some Old Type style, NEW Deluxe and New Improved custom made razors made for special costumers. Some were made from sterling silver.
This is a custom made New Improved full set:
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