Active tone control system, no noise, perfect for a electric violin. High quality silent EQ pick-up produces nice and charming sound. DIY your electric violin through the electric violin pickup outfit. With tone control & volume control, easy to adjust. With 6.35mm output and 3.5mm headphone jack, convenient to connect. Color: Black Material: Plastic + metal Tone Control: ±12dB Volume Control: 0-10 Frequency Response: 20Hz~20KHz Power Supply: 1 x 9V battery(not included) Note: This item is not including the battery. Package List: 2 Set Violin EQ Pickup (Not including battery) 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.