Dunlop DVP4 Volume X Mini Pedal
The AUX output combines tuner and expression functionality into one jack that can be toggled with a switch inside the pedal. When using the DVP4 as an expression pedal, you can use an internal pot to set the minimum level of the parameter you’re controlling with the rocker. If you want to reverse the function of the heel-down and toe-down positions, the DVP4 has another internal switch that allows you to do so.
Don’t sacrifice control over your volume level and FX pedals just because you’re using a travel-sized board. Get yourself a Volume (X) Mini Pedal.