B-Stock, Roadie Tuner, automatic tuner, the Roadie Tuner connects to your iOS or Android (4.3 or later) phone via Bluetooth, after strumming the string the tuner then tunes the string automatically, in addition to standard tuning and alternative tunings you can save custom tunings, the Roadie Tuner reports as soon as the strings need to be changed and can then be used as a motorized string winder. only works with the Roadie Tuner app, B-Stock with full warranty, may have slight traces of use