Features:      Mini guitar delay effect pedal with true bypass.      Pure analog circuit delay, clear, plump and smooth new delay effect.      3 control knobs: tone of delay effect, degree of feed back, time of delay effect.      With LED indicator showing working status.      Aluminum alloy body, durable and sturdy.         Specifications:      Input: 1/4'' Monaural Jack      Output: 1/4'' Monaural Jack      Time of Delay: 20ms-620ms      Input Impedance: 1M Ohms      Output Impedance: 490 Ohms      Working Current: 42mA      Power Supply: DC 9V (Plug polarity is positive on the barrel and negative in the center)      Item Size: 3.8 * 9.5 * 3.5cm / 1.5 * 3.7 * 1.4in      Item Weight: 210g / 7.4oz      Package Size: 6.3 * 12 * 6.5cm / 2.5 * 4.7 * 2.6in      Package Weight: 277g / 9.8oz         Package List:      1 * Effect Pedal      1 * User Manual (English & Chinese)         Note:      Please use the 9V power adapter whose polarity is positive pole outside and negative pole inside. Otherwise, the product may not work properly.