The 3 1/4" x 4 1/4" sheet film size has been obsolete since some time in the 1960s. There really was no need for a size between 2 1/4" x 3 1/4" and 4" x 5"./
As a result, 3x4 cameras are something of a drug on the market. I got this one very cheap, but was able to modify it into something actually useful.
I removed the original back, and installed a 2 1/4" x 3 1/4" Graflock type back from some junker or other, with the back oriented vertically. This allowed me to use 2 1/4 rollfilm backs on this camera.
I also installed a hot shoe, and a somewhat longer than normal 135 mm lens.
I had a couple of specific applications in mind:
I never wound up using this camera all that much in the end. It turned out that the film and processing was just getting to be too much to deal with. I also found the depth of field wasn't really adequate for the bike racing stuff, plus the lack of motor drive made it much less useful, and it was heavy to schlep around on bike race courses.
If you would like to make a link or bookmark to this page, the URL is:
https://sheldonbrown.com/org/cameras/speed-graphic3x4.html.