I bike chain is only one example (and size) of roller drive chain. Larger ones are used in motorcycles, and they are used in various pieces of equipment elsewhere. I have a tiny one which was used to transfer the rotation of a knob to the shaft of a switch somewhat remotely located. A larger one is used in the Logan shaper to drive the bull gear from the motor in the base.
Very likely.
O.K. The other size is a 7" one, so the part number may reflect that. Looking in an old Starrett catalog, I see that the wire cutters are "No. 1" (followed by some suffix), and the same plier bodies, but with tile-cutting blades, bears a "235" part number.
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It helps that I have bought them new, and thus gotten the instruction sheet which accompanies them.
I have now read what it is.
And this.
Out of curiosity -- why do you keep accepting guesses after you have posted the answers?
Enjoy, DoN.