41in Acoustic Guitar with Resonance Pickup Charging Adapter Cable Piano Bag for Music Lovers Item Type: 41in Acoustic GuitarPanel Material: Spruce veneer Back and Side Panel Material: Mahogany Fingerboard Material: Rosewood Neck Material: Mahogany String Material: Coated strings Battery Type: Rechargeable lithium battery 3.7V (delivered with battery) Battery Capacity: 1800mAHEquipped with Rp10 resonance pickups:Inner circle: a multi‑function volume button Middle circle: the effect dial with a total of 20 gears, which can be rotated 360 degrees to select different timbre effects.The outer circle: the indicator panel consisting of four sets of effect lights and a set of battery indicator lights. When the effect dial is turned to select an effect, the corresponding effect indicator will be lit.When the effect is in neutral, the four sets of effect lights will flash at the same time. Note: 2. Charge it in time after each use, and fully charge it at least once a month, the battery will be more durable. The circuit structure of RP10 is basically the same as that of a mobile phone charger. Please choose a regular mobile phone charging head or a power bank to charge this unit. 3. When you don't need to connect speakers or charge, you should unplug the connecting wire from the tail pin to prevent battery loss. This product does not include charging head and power bank. Only the charging adapter and audio cable are included!