JOYO JF-10 Dynamic Compressor Guitar Effect Pedal True Bypass, the representation of classic Ross with very low noise. It has Sustain, Attack and Level knobs. Attach is designed for the adjustment of Bass or high-output active pickups. True Bypass. Features: A re-creation of the classic Ross compressor, with very low noise. Use the Sustain, Attack, and Level knobs to find your ideal tone. Sustain: To control the delaying time of compressing; Attack: To control the starting time of compressing effect; Level: To control the output level. The Attack is especially designed for Bass or high-output active pickup. True bypass design minimizes tone loss. Aluminum alloy casing with stove varnish finish. Powered by a 6FF22 9V battery or 9V DC power adapter (adapter included). Description: Color: Green Effect pedal size: 11.8 x 6.4 x 3.8cm / 4.6 x 2.5 x 1.5in Effect pedal weight: 300g / 10.6oz Package size: 13 x 7.7 x 6cm / 5.1 x 3.0 x 2.4in Package weight: 330g / 11.6oz Package Includes:(1* JOYO JF-10) 1 x Effect Pedal 1 x MEC Power supply 1000ma (nice clean power) 1 x User Manual Note: Power supply not included. Please use the 9V power adapter whose polarity is negative center otherwise, the product may not work properly. Package List: 1 * Effect Pedal 1 * User Manual(English Chinese) 1 * Year warranty through our store No Duty to Canada and USA FAST 'N FREE USA Shipping (typically about 4 days) Ships from Canada