As mentioned before , a clean windshield to start and buffing it a little with a nice clean cotton rag. I notice at around 45 mph it starts to blow right off the windshield and is very clear, I put it on the goggles for motorcyling , skiing etc. It works great. Hans.

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A couple of Ford pickups F 150,250, 350 missed.
1983 240 D 256,000 miles ,auto, ac.