DOUBLE G0 pro Guitar Preamplifier BT Preamp Pickup Acoustic Chorus Delay Reverb Effects Soundhole Pickup with Receiver Built-in Rechargeable Battery for 95-110mm Diameter Sound-hole Guitar: It has various DSP effects including compress reverberation chorus and delay.With record and preserve function just connect your device with a suitable cable to the 3.5mm active recording output jack(4 channels).Comes with a wireless receiver for wireless output you can connect guitar to amplifier without cable.Cork pad clamp design no damage to paint of instrument.It supports active recording wireless output BT audio really a magical preamp.Support 2 different sets of BT transmissions at the same time. DOUBLE G0 PRO LE for connect for APP and it you want to input some beats or accompaniment via BT device connect it to the DOUBLE G0 PRO.Equipped with a gel pad which is washable and reusable convenient to use anywhere.With wireless transmission mode thus you can connect the amplifier through the wireless receiver.Sound hole installation no need drill hole easy to install. The preamplifier is suitable for mounting on guitars with sound hole diameter during 95~110mm.Both of preamp and receiver are powered by built-in polymer lithium battery. Battery is rechargeable large capacity long life and has stable performance.Receiver with 1/4 audio plug it can be connected to AMP or audio controller.Double+). Specifications: Material: ABS+PCB Item Size: 103 * 68 * 50mm / 4.06 * 2.68 * 1.97in Package Weight: 534g / 18.83oz Item Weight: 159g / 5.63oz Package Size: 17.5 * 15.2 * 5.5cm / 6.89 * 5.98 * 2.17in Battery: 2000mAh APP: Double+ Package List: 1 * Screwdriver 1 * Output Tail Nail 1 * Tail Nail Leather Cover 2 * Gasket 1 * Nano Pad 1 * Manual (English) 1 * Pickup 1 * Vibrating Horn 2 * Cable 1 * Receiver 2 * Clip Note: This product is a magnetic coil and microphone combination pickup which is suitable for all steel string guitars but not for all nylon string guitars.