The Boss TU-05 Rechargeable Tuner Clip-On brings reliable and accurate tuning to the headstock of your favorite stringed instrument, with a large, high-contrast color display and four different tuning modes. A long-lasting rechargeable battery is built in, eliminating the cost and hassle of battery swaps. Features Compact and accurate clip-on tuner with high-contrast color display Four tuning modes: chromatic, guitar, bass, and ukulele Adjustable calibration from 431 to 449 Hz Rechargeable battery with up to 10 hours of continuous runtime Auto power off feature conserves battery life when not in use USB cable included for charging with a standard USB power adaptor High Visibility in Every Environment The Boss TU-05 Rechargeable Tuner features a large color display with super high-contrast, offering great visibility for quick tuning anywhere you play, from dark stages to bright sunlight. The rugged, padded clip provides secure mounting on your instrument’s headstock, and the display can be easily swiveled for the optimum viewing angle. Rechargeable Battery A built-in rechargeable battery provides up to 10 hours of continuous runtime, and there’s an auto power off feature that kicks in when the tuner’s not active to conserve battery life. With the included cable, you can charge the Boss TU-05 Rechargeable Tuner with the same USB adaptor you use with your phone or tablet. Works with Guitar, Bass, Ukulele, and More With its versatile modes and quick-change design, you can tune a variety of instruments with the Boss TU-05 Rechargeable Tuner. Choose from standard tuning modes for guitar, 4- and 5-string bass, and ukulele, or chromatic mode for alternate tunings and other stringed instruments. Flat tuning over a range of three semitones down is supported, perfect for players who like to tune low for a heavier sound. And with adjustable calibration from 431 to 449 Hz, you can set the tuner to a reference other than the default 440 Hz standard if needed.