It use for Chromatic, Guitar, Bass, Violin, Ukulele. if you order more ,more favorite price. *A4 Frequency: 430-450Hz *Tuning Items: Chromatic, Guitar, Bass, Violin, Ukulele. *Tuning Range: A0(27.5Hz)-a3(1760Hz) *Weight:30g *Dimension: 80(L)×78(H)×24(W)mm *Power:CR2032 Battery 1 piece *Color: Black JT-13B tuner Tuning Items: Chromatic, Guitar, Bass, Violin, Ukulele.