Dimensions (W/D/H): 5.78 x 4.76 x 2.30 (146.8mm x 121mm x 58.4mm) Weight: 1.7 lbs. (771g) with battery, 1.6 lbs. (725.7g) without battery True Bypass Switching Battery Type: 9VDC (one) Power Consumption (Current Draw): 9VDC/25mA External Power Supply (Not Included): WARNING!!! To avoid immediate damage and voiding the warranty, the External Power Supply MUST be 9VDC with a NEGATIVE CENTER plug polarity and a jack plug size of 2.1mm x 5.5mm. Input Impedance: 1M Ohm (500k Ohm minimum) Output Impedance: 10k Ohm