This multi-functional Wah-Wah pedal offers everything you need for virtually all styles and sounds. This BEHRINGER product has been designed to compete head to head with leading products on the market. Different from most pedals the Hellbabe uses complete optical control for wear-and-tear-free pedal operation (no mechanical pots and switches) plus it features a unique spring-back pedal mechanism with resistance adjustment for the ultimate freedom in playing styles. The heel-down frequency range is freely adjustable using Range control (440 Hz to 250 Hz), so you can use it even with bass guitars. An additional Fine Tune control allows high-end extension of sweep range for achieving incredibly bright, ultra-present tone. The musical Q control is provided for precise filter shaping and achieving vocal-like effects. The tunable boost function includes an On/Off switch that lets you push your licks up to the limit. included dual LED indicators for Effect On/Off and Boost On/Off at the tail of the pedal. Only ultra-low noise circuitry is used throughout for outstanding audio performance. Run your HB01 on a 9 V battery or a DC power supply (not included).