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 (neither included).Specifications:Color: GreenEffect pedal size: 11.8 * 6.4 * 3.8cm / 4.6 * 2.5 * 1.5inEffect pedal weight: 300g / 10.6ozPackage size: 13 * 7.7 * 6cm / 5.1 * 3.0 * 2.4inPackage weight: 330g / 11.6ozPackage list:1 * Effect Pedal1 * User Manual