"6 tuning modes to choose from (chromatic, guitar, ukulele, violin, ukulele C, ukulele D). In guitar or bass mode, there is a flat Tuning options. For other stringed instruments like mandolin, banjo, use chromatic mode for tuning. Built-in high-sensitivity piezo pickups ensure extremely precise tuning. Display is rotatable and easy to read. Default pitch is 440Hz, But you can adjust it according to your needs between 430 and 450Hz. The small size is great for storage or travel (see photo size), but the large on-screen notes make it easy to read even from a distance. The one on the left The orange needle means the note is too low and the note on the right is too high. The green needle in the middle means the note is in tune. The tuner is made of eco-friendly ABS plastic with fine workmanship. The thick rubber pad on the clip protects the varnish of the instrument. It turns off automatically within 5 minutes without intervention to save power. Important: This tuner works with most stringed instruments such as guitar, bass, ukulele, violin, banjo, mandolin, etc. Not suitable for other instruments such as drums, saxophone, clarinet, flute, piano."