Korg GB1BK Folding Keychain/Pocket Tuner Convenient folding guitar or bass tuner that plugs directly into your instrument Supports 7-string guitars and 6-string basses; Flat tunings up to 7 semitones below original pitch Simple and portable design - attaches to your keychain or fits in your pocket. Easy-to-read meter; LED flash light for on-stage illumination. Available in Red, White and Black