I misplaced my normal cheapo guitar string winder, so I went to my junk drawer and found a couple I haven't used for a while. The yellow Dunlop was just like every other cheap guitar winder, but the black Fender winder had two different sized openings. I always assumed the openings were for Kluson style and the bigger one for Grover/Schaller type sealed tuners with bigger knobs. Just for fun I tried the smaller opening on my mandolin and it worked and still was able to clear the adjoining tuners.
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