This is the Synthesizers.com (Dotcom) QPCJA cable, that allows connection of a standard PC joystick to the Q142 Pedal Interface module. It's basically a breakout from the DA15 D-sub connector that goes to a generic joystick used with IBM PC compatible 'game port', to four 1/4-inch jacks that plug into the Q142 pedal interface Pedal 1 and Pedal 2 jacks (or could be used with any control voltage input). It's a cheap way to get joystick type control of your modular synthesizer, as joystick modules can be expensive and hard to find.