Features: (Same Frequency Trans) guitar preamplifier is a masterpiece of innovation that has a transmission device which drives guitar body to phonate when you are playing. System pickup guitar sound when you are playing guitar and drives guitar body through its custom transmission device. When operated without an amplifier guitar body will increase its frequency response and guitar sound will be more resonant solid and dynamic. preamp also has a DOUBLE reverb effect module that allows you to create innovative sound via transmission system driving guitar body. Equipped with BT connection function it can be connected to your cellphone and play with background . It is a dual-pickup system with a piezo pickup and a microphone system not only interprets every detail of play but also adds extensity and dynamic to sound of guitar. Specifications: Material: ABS Battery: 1 * 2000mAh rechargeable battery Item Size: 90 * 50 * 45mm / 3.54 * 1.97 * 1.77in Item Weight: 207g / 7.30oz Package Weight: 357g / 12.59oz Package Size: 17.5 * 12* 6cm / 6.89 * 4.7 *2.36in Package List: 1 * Pickup 1 * End-Pin Jack 1 * Vibrating Horn 1 * Pickup Wire 1 * Type-Cable 2 * Clip Note: This is an on-board preamp which needs opening holes to installation system. use of a microphone requires connection to speaker in order to be effective.