Trademark Tone Without The Hassle - more distortion than AC booster. The Bass BB Preamp distortion booster was designed to retain the original attack sound and tonal spectrums and produce a variety of gain structures for all bass players. Each of the two broadly-overlapping EQs offers 15dB of Boost or Cut. The gain knob ranges from a pristine clean boost to a hard overdriven distortion, with a very nice tone that stays firm, with great note separation and just the right amount of compression for a smooth overall texture. True bypass for eliminating any signal interference when it is switched out. Can be used with AC adaptor (optional) or 9V Battery

Specs Dimensions (W/D/H): 4.39" x 2.38" x 1.98" (112mm X 60mm X 50mm) Weight: 0.6 lbs. (280g) True Bypass Switching Power Consumption: 9VDC/8mA Battery Type: 9VDC (006P) x 1 AC Adapter (Optional): 9VDC, Negative Tips (Regulated recommended) Input Impedance: 500k ohm (min) Output Impedance: 10k ohm PDF page for more info