The black rail will be for a soft top or bikini top. It is actually a channel of which the tops slide into, before you fasten 'em tight at the rear.
I haven't seen the Quadratec reinforcement kit. Original equipment had a metal strip which bolted to the windshield and also the top. I have never used mine. No water leaks when raining, no wind noise that I could hear over the other wind noise around the doors,
. That reinforcement kit and my strip is just more work to do putting it on and off in my opinion.