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ProCo Rat2 3-Way Mod
Keeley Mod


The RAT has a classic tone to start with.  This pedal is now the culmination of many ideas and modifications.  Every component added is of the highest quality.  Film capacitors are used in the tone section to provide the smoothest midrange and high frequency components to your tone while increasing the bass response of the pedal.

What you get with the Rat 3-Way Mod!

  1. 3-Way Clipping Selection Switch
  2. Capacitor upgrades within the signal path to reduce noise and improve bass response as well as signal clarity.
  3. DC Jack is replaced with a standard barrel plug adapter
  4. Blue Led
    The 3-Way switch on your pedal offers you the classic Rat as well as two other modes.
    1. Switch to the Left (or down if you have a large box Rat) – This is the classic RAT sound, you benefit from the increase in bass response dues to the capacitor changes we make. The volume will seem low compared to the other modes but this the stock RAT output level.
    2. Switch to the Right (or up if you have a large box Rat) – This is the PHAT RAT mode, normally the Rat has two diodes in the circuit for clipping, we add one to add a tube type tone. The volume is increased slightly and there is an added richness to the tone.  Fatter and more complex is the tone you get from this mode.
    3. Switch in the Center -- This is the Mighty Mouse mode.  Super volume output.  We take out a diode from the circuit so this thing is raging with volume.  Great natural sounding gain.  Enough volume to drive any amp into true overdrive.

      All modifications are warrantied for you, the original owner, for one year. If you have any problems at all please email Mammoth Electronics at If you are happy with this product, please let everyone know and tag us on Instagram and Facebook with #mammothelectronics. If you are not happy with this product for any reason at all, please let us know within 48 hours and we will refund your order. The entire Keeley and Mammoth team thanks you for your business. You’re keeping the good tones alive! If you like this product, there’s more where it came from, check out the rest of our products at

      Mod times are 3-5 business days from the day that your pedal(s) arrive. Please ship to the address below:

      Mammoth Electronics
      Attn: Mods Department
      3203 Broce Dr
      Norman, OK 73072

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