112mm BB axle

Lets start with some tech info:

J.I.S. is the Japanese Industrial Standard, and on square taper cranks, so Shimano and various other brands from asia.
ISO square taper spindles run longer, and taper down to a smaller end than J.I.S. spindles do. Most European-made square-taper cranks and bottom brackets use the ISO dimensions. so Campagnolo
The difference is across the axle flats, and it's minimal J.I.S being slightly smaller.

So If you run the the wrong set up, some cranks will bottom out at the end of the axle, thus not being able to secure them properly, and then the bolt works loose, followed by the pedal arm falling off!

The bottom bracket in question is a size used on MTB, Shimano did/do a 113mm axle and I remember fitting quite a few of them to MTB's
 
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