The Maestro Mariner Tremolo offers two amp-like tremolo options for two pedals in one functionality and increased sonic versatility. Classic mode: you can swing from subtle, smooth amplitude modulation all the way to a sharper-edged, saw-biting modulation. Harmonic mode: you can dial up timeless textural Harmonic Tremolo tones reminiscent of tones produced by vintage amplifier tremolos. • MFSKU MOCMTP • UPC 711106088242