PS-1 high-quality sustain pedal features a polarity switch, it applies to keyboarder or musicians who pursues realism pedal touch. PS-1 adopts the same working mechanism as piano pedal, the classic style with universally compatible making it virtually match to any piano or keyboard. PS-1 sustain pedal is designed to work and feel just like the sustain pedal on an acoustic piano. Specially designed rubber bottom grips the floor and stays put while you play. The heavy-duty spring allows for better control and playing longevity.