[Jack Zupan]

The tensor bar is made to insure that the stress on the windshield frame is spread evenly. If you are moving at speed with a top on the car, there is a lot of stress pulling at single point which can separate the frame from the glass. The tensor bar spreads that stress to the entire frame. SPF first epoxied the glass to the frame as a fix but this is a problem if you have to replace the windshield. I understand that several British sports cars from the 60's had them a well.

Jack Z.