Using the Ernie Ball Power Peg Pro is easy. First, plug it in with the included USB - C cable to charge the lithium - ion battery. Once it's charged, you're ready to go. Simply attach the universal head to the tuning machine of your guitar, mandolin, ukulele, or vintage bass. Then, start the winder, and it'll quickly restring your instrument. When not in use, store it in a dry place. To keep it in good condition, avoid dropping it or exposing it to extreme temperatures. And don't forget to charge it regularly so it's always ready when you need it.