Boss EV-30 Dual Expression pedal. For pro expression control in a compact package, there’s no better choice than the BOSS EV-30. Its small footprint is perfectly suited for cramped pedalboards, while the die-cast aluminum chassis offers a rock-solid foundation and BOSS's famous rugged reliability. A key feature of the EV-30 is an innovative internal mechanism that provides ultra-smooth feel and precise parameter control, delivering performance that rivals full-size pedals. And with two expression outputs, you can save further space by controlling two different devices from a single pedal. The outputs are electronically isolated, eliminating the possibility of noise issues from ground loops. The EV-30 brings powerful real-time parameter control to the many BOSS compact pedals equipped with expression pedal inputs. It's also ideal for use with BOSS multi-effects processors and effects switching systems. A handy polarity switch provides compatibility with a wide range of music gear, allowing you to use the EV-30 with most devices that support expression control.