Features: Classic optical compressing sound with smooth attack and decay, preserves the signal transients perfectly. True bypass design. Mini and exquisite appearance. Aluminum alloy housing. Comp, EQ, Volume control knobs: Comp: Adjust the intensity of compression; EQ: Adjust tone of sound; Volume: Adjust the output volume. Specifications: Color: Yellow Suitable for: Electric guitar Material: Aluminium alloy & PCB Input: 1/4" monaural jack (impedance: 470k Ohms) Output: 1/4" monaural jack (impedance: 1k Ohms) Power requirements: AC adapter 9V DC Current draw: 10mA Item size: 9 * 3.5 * 3.2 cm / 3.5 * 1.4 * 1.3in Item weight: 146g / 5.2oz Package size: 10.5 * 6 * 4.6cm / 4.1 * 2.4 * 1.8in Package weight: 169g / 6oz Package List: 1 * Optical Compressor Pedal 1 * User Manual (English & Chinese)