This switch is actually an on/off switch for a Prince Castle 197 Toaster. After talking to their tech support team, all they could tell me is that the unit it's designed for uses a 120V circuit. Since you plan on using it on a musical instrument, it impossible for us to ensure that it would work, or that it would even be safe. However, if you know a lot about electronics, you might find some more info on this spec sheet from Prince Castle. Here is the link
http://www.princecastle.com/pdf/man...