Q: Does it fit mandolins well?
A: It will fit most standard type Mandolin tuners.
Q: How wide is the tuning peg opening?
Q: Does it fit classical guitar pegs?
A: Yes, it fits most all standard type classical tuning machines.
Q: Will this work with the smaller pegs?
A: Yes, it fits most small style tuning machines.
Q: Will it fit tuners on an upright bass?
A: Yes, the slots on the side will accept the large paddle.
Q: Will it work for banjo style tuners?
A: It will work on standard tuning machine on the headstock. It will not work well on friction tuners.
Q: Does this work on violin and viola pegs?
A: Yes, but they are friction pegs. This winder is designed for gear tuners.
Q: What is the hex wrench on the end for?
A: It is a 10mm for tightening the most popular tuning machine bushings size found on electric and acoustic guitars. They should be tightened just beyond hand tight every string change as they get loose from playing your instrument. Don’t over tighten. Most people never check these but you should as loose tuners can cause buzz, reduced sustain, tuning stability issues.