Before you buy a piano pedal, ask yourself this: do I know the polarity of my piano? You're probably thinking something like, 'Yeah, sure I do ; it's filed in my brain right between my social security number and my bank PIN.' But seriously, this is important. Now, you could run off in search of your manual, or you could do yourself a favor and just buy an M-Audio SP-2 Sustain Pedal in the first place and save yourself the trouble.