Expression Pedal Single Output from Electro-Harmonix

from the EHX website:

“A single-output pedal that’s versatile enough to control virtually any device with an EXP input. Built to be both versatile and affordable, the EHX Expression pedal can control expression parameters on a wide array of products from various manufacturers as long as the product includes an expression jack. The TRS polarity switch provides the ability to change the connections to the TRS jack while a Reverse button and a Range knob allow the musician dial in the perfect expression sweep for their application.