Glass loses its clarity through abrasion from wipers and seals. Windscreens are made of fairly soft glass, so the problem is common. Polishing with cerium oxide paste removes the scratches while keeping the surface optically clear.
Most windscreens have fine scratches 50-200 microns deep from the wipers rubbing. We remove a thin layer of glass and bring the clarity back - at a far lower cost than replacing the windscreen.

