I have a Morley Pro Series Optical Volume for Sale(it is not a Wah Pedal). Players wanting a simple, reliable volume pedal will love this Pro Series Volume, a beefy unit built like a tank to withstand the abuse of even the roughest of gigs and tours, as well as a smooth transition that will make the volume effect sound amazingly natural. It plugs in between the instrument and amp on the pedal board.
Yo can notice the marks on the bottom, however they don't affect the operation of the unit. It is in good condition and I was using it for guitar and my Yamaha keys. I switched to CC Expression pedal. I do not have a power supply(9V Neg center, very common.; also runs on 9v battery). On eBay and Reverb, Pedals like this are selling for $75+