Compact guitar/bass auto-tuner compatible with 5-string/6-string basses (Low B, High C) and 7-string guitars (Low B). Features include a highly visible pitch indicator & tuning guide, and a built-in microphone for acoustic instruments. Display: Pitch indicator, tuning guide Strings: Guitar 7B, 6E, 5A, 4D, 3G, 2B, 1E Bass LB, 4E, 3A, 2D, 1G, HC Reference pitch: A4=440Hz (fixed) Power: 1.5V AAA (R03/LR03) batteries x 2 Thank you for viewing. Please refrain from purchasing if you are sensitive to items that have been stored at home for a long time (⁎ᴗ͈ˬᴗ͈⁎) #Tuner #Tuning #YAMAHA