Size 124. Spool looks like 620 with a pituitary tumor -- flat metal end flanges, narrow spindle (though with this level of magnification, the core has a wood dowel for about 2/3 of its length, on original film). Kodak sold a number of folding cameras to use this size.
I think it was four inches wide, six frames on a roll (so about the same length as 120; you could hack a Paterson reel and core). but there was also five inch unbacked long-roll film made for surveillance cameras. Most would have been aerographic emulsions, with "funky" spectral sensitivity, but a little filter will fix that.