Joyo JF-10 Dynamic Compressor Guitar Effect Pedal True Bypass True bypass design to minimize tone loss9V power via batter or power supplySustain， level and attack adjustmentsAluminum alloy casing with stoving varnish finishA 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 / 11.6oz