The ERNIE BALL POWER PEG is a battery-powered, motorized guitar string winder. It is a luthier tool designed to make string changes fast and easy. The POWER PEG can wind your guitar strings at 90 RPM, which is three times faster than manual winding. The POWER PEG is an ideal tool for guitar technicians, guitarists, and bassists who need to change strings frequently. It is compatible with all electric and acoustic guitars and basses. The unit is easy to use, and it can wind strings in both directions. The POWER PEG is made in the United States by ERNIE BALL, a trusted brand in the music industry.