Walrus Audio Fathom Multi-Function Reverb Effect Pedal With Box - UsedThe Fathom Multi Functional Reverb features different four reverb program modes: Plate, Hall, Lo fi, and Sonar, with a control knob labeled "X" to adjust the effect within each mode. Momentary functions can be triggered by pressing and holding Bypass Switch to temporarily activate the effect to add a moment of reverb, or by pressing and holding the Sustain Switch while the pedal is on, to sustain the reverb decay for a dreamy ambient decrescendo. The