The Planet Waves Tuner-Up improves any acoustic guitar tuner's performance, especially in noisy environments. The Tuner-Up bracket's patented design features a built-in piezo element that senses pitches directly from the guitar's top and passes them directly into your favorite tuner. Fits most common tuners, and is perfect for acoustic guitars without pickups. Includes a 1/8" male to 1/4" female adapter for plugging into your tuner.