This one is interesting in that the lens has what appears to be a Jacobson Synchronizer that is a spitting image of the one in patent #2151355 stamped "IRVING MFG CO" and has a focal plane shutter flash synchronizer that appears to be the one described in patent #2406691, with the connectors for that also labeled "IRVING MFG CO". There's some other oddities such as the focal plane shutter table being over by the optical viewfinder, and the rangefinder placed so that an extension tube interferes with the operation of the focal plane shutter cocking knob.
My theory is that this could be a special customized by Irving Jacobson when he worked at the Western Division, since that top plate doesn't look like it was moved.
I've taken some pictures, which are in an album at https://1drv.ms/a/s!As1wu6G89QtTkMdQzJmIpzTEpBT_Yg?e=o8itwi but since the URL tag is off, I'll attach a couple here.
- Synchronizer-small.jpg (182.9 KiB) Viewed 8761 times
- TopView-small.jpg (237.81 KiB) Viewed 8761 times
- IrvingConnector-small.jpg (163.38 KiB) Viewed 8761 times
