Jim Dunlop - Volume (X) 8 Pedal.  Combination volume and expression pedal in an 8" housing to give you the most efficient use of your pedalboard space.  Patented low friction Band Drive. Internal controls set the expression's mode minimum effect level parameters and the rocker's heel/toe polarity.  Fully adjustable rocker tension.  External jacks for volume, EXP, output and tuner output.