Designed and Handcrafted in Petaluma, California, USA. True Bypass On/Off Switching - Bypasses all circuitry when off to ensure no tonal loss. Input Level Control provides Unity Gain Detent and ability to boost by +6dB or cut by -40dB. Output Level Control provides Unity Gain Detent and ability to boost by +6dB or cut by -40dB. Slider Controls provide Mesa’s legendary tone-shaping power with +/- 12dB of boost or cut at 80Hz, 240Hz, 750Hz, 2.2Khz and 6.6Khz. On/Off Status LED. 9V Battery Powered or Externally Powered (optional) via External Power Jack Input. Input & Output Jacks (Nominal Input -20db).