Morley M2VO passive volume pedal

The M2VO operates without the need for a battery or external power adapter. Simply plug your instrument into the IN jack and connect the amplifier to the OUT jack, and you’re ready to go. 

M2 Passive Volume Guitar Effects Pedal. Smooth audio taper in this passive volume pedal (no power required). Simply plug in, and you're ready to play. Cold-rolled steel housing and two-year warranty. This in-line volume pedal delivers a consistent, smooth response that is easy to use and predictable for ultimate expressiveness.