This item is from my family. KORG GA-1 guitar/bass tuner with sound adjustment function, uses AAA batteries. - Model: GA-1 - Brand: KORG - Type: Guitar/Bass Tuner - Features: Sound adjustment function - Power: AAA batteries x 2 I'll include the used AAA batteries as a bonus, though I'm not sure how much charge they have left. The battery compartment lid feels a bit stiff to open and close (in my personal opinion). Operation has been confirmed. This is a used item, so there are some minor scratches. Please refrain from purchasing if you are concerned about minor details. Please ask any questions you may have in the comments.