Updated version of Maxon OD820 Combination clean booster/overdrive Switchable 9 or 18 volt operation using internal voltage doubler Reacts precisely to picking dynamics True Bypass Switching Specifications Input Impedance: 500K ohm Output Impedance: 10k Ohm Maximum Gain: 46 dB (1.5 kHz) Equivalent Input Noise -112 dB or less (IHF-A) Controls: DRIVE, TONE, LEVEL Operating Voltage 9V Power Consumption 30mA/DC.9V Switch: Normal/Effect (true bypass configuration w/4PDT switch) Power Supply: 6F22 9V Manganese dry cell battery x 1 or Maxon AC adaptor (not included) Dimensions: 2.9" (W) x 4.9" (D) x 2.1" (H) - 74 mm (W) x 124 mm (D) x 54 mm (H) Weight (w/o battery): 20.5 oz Accessories: 9V Manganese dry cell battery, Users Manual, Warranty Card Specifications subject to change without notice.