Our guitar tuner has a built-in rechargeable battery, no need to replace button batteries, and it is very environmentally friendly. Quick charge on computer or power bank with USB cable, lasts 10+ hours on a single charge The violin tuner can automatically power off after 5 minutes of no signal, saving energy. The clip-on guitar tuner has a note key function, which can meet the needs of most professional guitar players. When the device is in G (guitar) tuning mode, short press this button to switch between guitar tuning (DROP D, OPEN G, OPEN D, OPEN E) and drop (b, bb). With this function, you can play more songs. Highly sensitive vibration-based tuning ensures that your instrument is tuned quickly and accurately, even in the presence of background noise. Unlike other cheap tuners, this guitar tuner reads the bass guitar's low E string quickly and flawlessly, with no stutter at all. The ukulele tuner is virtually frameless and features a large LCD color display that is easy to read even in dark environments. With the 360-degree rotatable clip, you can position the screen any way you like. The tuner clip is well designed and small enough to fit in your pocket or the end of your guitar case. This violin tuner has four tuning modes (chromatic, guitar, violin, ukulele) and covers a wide variety of instruments including mandolin, banjo, and virtually all acoustic and electric stringed instruments. Comes in an elegant gift box to surprise your loved ones