The Pratt Hobbies GO Box is a simple, sturdy launch controller that is powered by your car's battery. (Which you conveniently charged on the way to the launch!)
After a slight glitch with my home brewed launch controller, I found myself in the market for a replacement. I had seen a prototype of Doug's GO Box at a launch and decided that it would fit my needs nicely. Just as importantly, the price was reasonable.
The GO Box came with a two page sheet of instructions, not that they are really needed. The controller comes with a 10 ft. cord that plugs into a standard center-positive cigarette lighter outlet. It includes a launch button, continuity sensing with a nice loud buzz, and a phono plug that connects to the 25 ft. long lead wires. This connection also doubles as the safety interlock. This is simplicity itself. As Doug points out, you can't fire the igniter if the controller isn't connected to a power source. I specifically bought this controller because I wanted to use my car's battery. However, it would be simple to build an adapter to a stand-alone battery or battery pack.
I have used this unit periodically (since I don't have a "solo" launch site, my opportunities are limited) for some time and am quite happy with it. I plug the unit into the car and run the controller through an open window. No more opening the hood and attaching battery clips. I've successfully used the GO Box with Estes igniters, Copperheads, Apogee's igniters (for the 10.5mm motors), and home-grown IgniterMan igniters. The engine range has been A - F. One jaw of each alligator clip came insulated with shrink tubing to facilitate the use of Copperheads.
I know this is a short review, but the GO Box is not complicated. In summary, it plugs into a cigarette lighter socket, is sturdy enough to take some knocking around, has nice long leads, you can hear its continuity indication in the brightest sunlight, and you will never misplace the safety key. I give the GO BOX a "5". (pictures used with permission of Pratt Hobbies)