Maker: Brockway Director
Visual Designer: Alpheus Maple
US Design Patent #: D154558
Price (new): $32.95
Cell type: Selenium
Measure type: 3D incident (2D incident and Reflecting/Averaging available with accessories)
The difference between these Norwood models is negligable. The Model C was simply the B with a new name plate to reflect the company's name change from American Bolex to Director Products. The Model M2 was a Model D with a new nameplate reflecting the company's name change to Brockway (even though the Model D says "Brockway" on the front).
But the Model D actually had something new besides the company name and a revised nameplate: it's a Color-Matic (there were some later C's that were Color-Matics, but they weren't formally designated as such).
Color-Matic was a gimmick to cash in on the growing popularity of Kodachrome film, which was available at ASA 10. Norwood came out with a special slide that was set for ASA 10 at 1/50th. It was painted red so you couldn't mistake it for anything else (the normal slides were black). If you used that slide, you could direct-read the new ƒ/stop scale next to the meter needle.
This meter suffers from the same problems that afflict the previous version: the calculator dial has tiny numerals and it can be tough to read. I have a lot of trouble reading the ASA indicator in anything but very bright light. The Sekonic version had a revised dial and the ASA indicator was a bit more legible.