High Quality: the pickup with a piezo pickup stick can connect external amplifier via the cable that has 1/4 inch jack, provide and clear sounds. Easy to Use: it is easy to control volume, bass, treble and phase via key and knobs, to acquire wanted mixed voice; and a light indicates battery status. Hassle-free to Install: just a few simple steps can install the sound control module of soundhole with included adhesive pads. Long-endurance: power supply of 2 x CR2032 button cell ensures it continuously works for nearly 80 hours; and it is convenient to replace batteries. & Portable: small guitar pickup, measures 8 x 6 x 3cm in size and about 2.50oz in weight, suitable for acoustic guitar. Model: B1G Power Supply: 2 * CR2032 Button Cell (Not included) Product Weight: 71g / 2.50oz Product Size: 8 x 6 x 3cm / 3.14 x 2.36 x 1.18in Note: Pickup set only, other accessories in the pictures are not included. Please read the user manual carefully for more information before usage. Color: As Shown Material: plastic Package Contents: 1 set * pickup (without 2 * CR2032 button batteries) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.