They have a wire, but the bob-cat adapter cost an extra $200. It works like a peach. In the cab, there are three buttons that control wiring harness controlled devices. I just push the left hand switch down, and the aux. hydraulics open and close the lower jaws. Push it up and they control the grapple.
I was planning on getting a grapple eventually (rented one the first week), just needed the puller first. When I saw the grapple attachment for this one, I decided to try this. It works very well. I will probably hold off on the grapple for now. So far, this does every thing I need, and I don't have to switch between implements after pulling stuff.
I also got their land leveler. Very nice product with a hydraulic actuated scarifier, with adjustable depth shanks. Haven't used it yet (just got them yesterday) but will post pictures when I do.