The Moog Moogerfooger Low Pass Filter contains 2 complete modular functions: a voltage-controlled lowpass filter and an envelope follower. Use with any instrument- or line-level signal, and the MF-101 is ready to be tweaked for classic Moog filter guitar effects.Cutoff rotary control Resonance rotary control Envelope Amount rotary control Mix rotary control Drive rotary control Smooth-fast rocker switch 2-pole/4-pole rocker switch 3-color LED to set Drive control On/Bypass switch 1/4" audio out jack 1/4" audio in jack accepts any instrument- or line-level signal Cutoff, Resonance, Amount, and Mix 1/4" jacks that accept moogerfooger EP-1 or equivalent expression pedals Envelope out jack delivers the envelope control voltage for use by other voltage-controlled devices Power adapter included