Blundell

Blundell S125 (probably)

This is a little rule, just a 5" scale and only 3mm thick, but it's super clean, very accurate, and easy to read. It doesn't have any manufacturer identification, but David Weymouth's excellent site shows a Blundell S125 with a slightly different construction but identical scales. I have not been able to identify the "EJW" logo printed on the back - drop me a line if you know.