You know when you try to put your briefcase on the rear rack? You strap it on with bungees and it's OK but wobbles a bit? Well, hold my beer, put this on and you get butterfly wings that extend sideways to support the briefcase, and it folds away when you don't want it! I've used one in the past and they're great. This one has never been used. It's still in its bag and comes with all the mounting brackets, screws and an Allen key.
