Features 1、Auto wah effect pedal, ideal for using with guitar or bass. 2、100% true analog circuit provides a lush warm sound. 3、4 control knobs(SENSITIVITY, Q, DECAY and TONE) make the pedal very versatile. 4、 size and full metal shell, portable and durable. 5、With true bypass footswitch and LED indicator light. Specifications: Features: Auto wah effect pedal, ideal for using with guitar or bass. 100% true analog circuit provides a lush warm sound. 4 control knobs(SENSITIVITY, Q, DECAY and TONE) make the pedal very versatile. Micro size and full metal shell, portable and durable. With true bypass footswitch and LED indicator light. Control Knobs: SENSITIVITY-- adjusts the dynamic response of the envelope filter in relation to the input from the instrument Q-- Clockwise will make the Q value higher, providing a more narrow frequency band with a higher peak; Counterclockwise will lower the Q value, providing a wider frequency band with a lower peak DECAY-- adjusts the release and closing of the filter TONE-- adjusts the overall tone and frequency range of the pedal Specifications: Material: Metal Signal Input: 1/4″Monaural Jack (impedance: 1Meg Ohms) Signal Output: 1/4″Monaural Jack (impedance: 1K Ohms) Power Supply: DC 9V adapter (center minus plug)(not included) Working Current: 20mA Item Size: Approx. 3.5 * 9 * 3cm / 1.4 * 3.5 * 1.2in Item Weight: Approx. 150g / 5.3oz Package Size: 10.5 * 6 * 4.5cm / 4.1 * 2.4 * 1.8in Package Weight: 175g / 6.2oz Note: The power adapter is not included. Please use the power adapter whose polarity is positive pole outside and negative pole inside. Otherwise, the product may not work properly. Package List: 1 * Effect Pedal 1 * User Manual(English & Chinese) Package List 1 * Effect Pedal 1 * User Manual(English & Chinese)