SODIAL(R) Acoustic Guitar Pre-wired Preamp 5 Band EQ Tuner Piezo Pickup 5-band tone controls (BASS, MIDD.1, MIDD.2, TREB., PRES.) Used for acoustic guitars who are looking to improve the sound Pre-wired for easy assembly / Supplied with a battery box Includes connecting wire with 2.5mm plug / Low battery indicator It measures about 58mm wide, 98mm long and 67mm thick