Out of my Dodge, no longer need it because the Silverado has the integrated one and it seems to work well.

It was one step below the Prodigy (no digital display), right around ten years old; but it worked fine when I pulled it. Its an inertial-based controller...you "level" the controller, which can make braking more/less aggressive, depending on your liking; and then you set how much power is applied to the magnets. I had really good luck with this controller, it always did the job. Again, this was one step below the Prodigy, and ran about $125 new. Will post up pictures upon request, but its just a controller.

Asking $40 shipped via USPS. Money order only. Located north of Reading, PA if you want to pick it up.