My latest acquisition: an Exakta Varex. According to the serial number built in 1952 with a Zeiss Biotar 58mm F/2 lens. At the time one of the most sought after cameras.
The protrusion on the lens caught the shutter release to trigger the aperture setting. Focussing could be done wide open.
Optional for this model (and later standard in the Varex VX II) was a prism viewfinder. The fresnel matt screen for "waist level" focussing in a light shaft could be replaced.