Features: 2 working modes: Up / Down. Specializes in generating super-funky wah-like tones. Magnalium alloy housing, good durability. Mini size, compact and space-saving. Durable jacks and foot switch. True bypass design, minimizes tone loss and get more control of your pedal. Designed with on / off LED, instructs effects or bypass status. With 3 adjustable knobs: level, peak, sens, 0.25in monaural jack. DC 9V adapter power supply, polarity is positive pole outside and negative pole inside available. Specification: Material: Magnalium Alloy Input: 0.25in monaural jack Output: 0.25in monaural jack Power Requirements: AC adapter 9V DC(polarity is positive pole outside and negative pole inside available) Current Draw: 10mA Product Size: 9.1 * 3.6 * 3.6cm / 3.6 * 1.4 * 1.4in Product Weight: 145g / 5.1oz Package Size: 11 * 6.5 * 5cm / 4.3 * 2.6 * 2in Package Weight: 168g / 5.9oz Package List: 1 * Auto Wah Pedal 1 * Cloth Bag 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.