Kidlex, I believe you are referring to the "AutoTrans Interceptor" - sold on
www.pfyc.com - it lets you adjust the line pressure on your transmission. The interceptor may sound cool, but I've read lots of stuff over on some other grand am forums (not allowed to name, PM me if you want links) of people that have had trouble with it. It's been known to increase the line pressure too much, which can cause tranny damage. It's really not a necessary mod, and everything I've read about it has pretty much been bad. Sorry to let you down, but I really don't suggest buying one.