1、Tone and volume control make music playing control better. 2、It has phase and tuning function, built-in reverberation, delay, Chrous and wide effect. 3、Installed on acoustic instruments (such as ballad guitar, classical guitar, etc.) for PA, the original sound into acoustics. 4、Volume amplification, effect can be used with effect equipment, enrich the sound of musical instruments. 5、The product is easy to install and has high fidelity to the original sound. Feature: Tone and volume control make music playing control better. It has phase and tuning function, built-in reverberation, delay, Chrous and wide effect. Installed on acoustic instruments (such as ballad guitar, classical guitar, etc.) for PA, the original sound into acoustics. Volume amplification, effect can be used with effect equipment, enrich the sound of musical instruments. The product is easy to install and has high fidelity to the original sound. Easy to use and understand. Specification: Input impedance: 10M Frequency response: 20Hz20KHz Control range: low: +/- 12dB at 100Hz; middle: +/- 12dB at 800Hz; high: + / -12dB at 3KHz Low battery check: LED Power: 9V alkaline battery Size: 83 * 62.8 * 47.5mm / 3.3 * 2.5 * 1.9in Weight: 185g / 6.5oz Package list: 1 * EQ Equalizer 1 * Battery box(No-include battery) 1 * Bar  9 * Screw Note: The actual product color may deviate from the photo due to light. There may be a slight deviation in the measurement of product.