good quality and beat price. JT-23B Specifications: *A4 Frequency: 430-450Hz *Tuning Items: Chromatic, Guitar, Bass, ... *Color: BlackJT-23C Specifications: *A4 Frequency: 430-450Hz *Tuning Key:C,F,Bb,Eb *Tuning Mode:MIC,CLIP *Semitone flat:b ... (W)mm *Power:CR2032 Battery 1 piece *Color: Black JT-23B digital tuner