This is the classic SansAmp, a 3-channel model. It was convenient for switching instruments, as well as for setting individual parameters for pick and fingerstyle playing. I have confirmed that all knobs and channels are working. In the past, the footswitch for the rightmost channel was not working well. It's not that noticeable at the moment, but it could happen again. Please be aware of this. This is for the unit only. Thank you.