I have no knowledge of how it works but it looks to be similar to a slide rule. It is in excellent condition. Hopefully, it will be of interest to a collector.
Vintage Nebro Visual Exposure Extinction Light Meter
Vintage PORST Analog Exposure Meter - Collecting Vintage Photography
Vintage General Electric Exposure/Light Meter DW-68 With Case tested working
Vintage General Electric Exposure/Light Meter DW-68 Working
Vintage Gossen Lunasix 3 Exposure Meter w/Case & Strap ~ UNTESTED
Exposure Meter Actino vintage 1950s German Used In Photography
