This is a DX2 controller by the legendary Faderfox. Pretty rare to see these offered secondhand, because most of them have found their forever homes.
Made in Germany, this bulletproof little tank of a controller feels great and will last a lifetime.
This one has MIDI i/o, which is honestly the most reliable way to use a controller.
Originally this was designed to complement Traktor DJ Studio, but there's nothing stopping you from choosing your own mapping, as it has 5 pushbutton rotary encoders, 4 absolute mode rotary pots, and over 3 dozen pushbutton controls.
If you're into custom mapping (I am), then the world is your oyster.