There is a small crack in the 4x4 conversion back so only graflok should really be used (not the spring back attachment that Graflex made). Of course you can use at your own risk, but I would stick to the graflok (and of course I will not accept a return for this if broken where I show the weakness has occurred).
You may be able to glue this and use it but this again is at your own risk. All shutter times sound good and the shutter cloth is in lovely condition, but I would suggest a CLA to ensure they are on point. I have tried slower speeds but not the fastest (1/1000) but exposures came out beautifully on these speeds and this lens creates stunning imagery. The 1/1000 sounds really good though (it wasn't bright enough to test).
Grab yourself an absolute bargain as this is a rare example, and the perfect way to get into premium large format film photography. The item "Graflok back Graflex RB Super D 4x4 Film Camera Kodak 152mm f4.5 Lens 4x5 film" is in sale since Friday, May 1, 2020. This item is in the category "Cameras & Photography\Film Photography\Film Cameras". The seller is "nickwhite19" and is located in Holmfirth.
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