Mooer Mooer ABY MK2 Switch Effects Pedal Signal path can flow from A/B to Y, or from Y to A/BCan work without power supply (LED will not be lit up)Full metal housingSpace-saving sizeTrue bypass DCRequires 9-volt Adapter power supply The signal can flow from A or B to Y, or the signal can flow from Y to A or B The pedal can work without power supply but the LED will not light