The Argus A2B was a variation on the original Model A. It came out in 1939 and added an extinction type exposure meter to the basic Argus A body. My copy is from 1940 and is still the original version with the uncoated lens and black faceplate.
Like the Argus A, it's a nice small package, especially with the lens collapsed.
The back has a fantastic Art Deco design.
The extinction meter is an interesting contraption that was built into a few cameras around this time and you could also buy separately from other vendors. It basically uses a strip of plastic or celluloid that you look through that has gradations of opaqueness.
First you set the topmost north-south slider to your film speed. 72 is the highest they went in 1939, and it's close enough for ISO 100 film. Then slide the bottommost north-south slider so that the little arrow on the bottom is pointing at either Bright, Average, Cloudy or Light Interior as applicable. Then you look through the meter and decide which of the graduated rectangles you can just barely see light through, then align the east-west sliding pointer with that rectangle. You then see the range of f-stops that line up with the shutter speeds in the column directly to the left of the north-south bar. You can understand why they quickly moved to selenium meters!
The pictures taken with the A2B can be quite good if you're careful to avoid flare with the uncoated lens.