Seymour Duncan 11900-003 Pickup Booster Pedal w/ 2 Patch Cables Type of circuitry: Fully discrete, Class A Gain range: 0 to 25 dB Bypass: True bypass Pickup Resonance Switch: Makes a single coil pickup sound like a vintage humbucker ("1") or high output humbucker ("2"). Frequency Response: -3dB at 30Hz and 38 kHz