Maker: G-M Labs
Model: Standard Model B
Price (new): $14.95
Designer: Archie McMaster
US Patent: 2,308,469
Cell type: Selenium
Measure type: Reflecting/Averaging
GM Labs in Chicago got every bit of its design investment back on this meter. This meter is virtually identical to their post-war Skan, the only visible difference being the cosmetics on the front nameplate and the rear dial. In fact, the only difference between this Model B and the Model A is the dial.
I believe they sold a raft of these things. I see them all the time on eBay. The bad part is that their value is virtually nil, other than fun collectable value or as a paperweight.