First if you should have gotten the person's tag and then made him pay for you to get a new windshield. Perhaps you insurance may cover it though, none the less. If its a deep crack I would recommend getting the windshield replace because it could get worse and shatter complete while you are on the road. But for scratch remover you can go to AutoZone and find some.
A four inch scratch is really big, probably too big for any scratch remover to fix correctly. What you need to do is take your car in to a place that fixes glass. They should have the correct tools to fix the issue.
There are several effective metal scratch remover products available on the market, such as the 3M Scratch Remover or the Turtle Wax Scratch Repair Kit. It is recommended to read reviews and compare products to find the best one for your specific needs.
In a shop...
Try: NOVUS PC-20 Plastic Fine Scratch Remover or Quixx Paint Scratch Remover All the best
Information on glass scratch removers can be found on manufacturer websites, online reviews, and in product descriptions from retailers like hardware stores or automotive supply shops. Additionally, tutorials and how-to videos are available on platforms like YouTube for guidance on using glass scratch removers effectively.
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There are many online websites which sell scratch remover, such as Amazon. It can also be found at Walgreens and Walmart, and in most hardware stores.
The best stainless steel scratch remover on the market is the Bar Keepers Friend Soft Cleanser.
You can go to gamestop.com and search for disc scratch remover. If you do not find it there, search it on SHOPPING on Google.
The scratch remover wood is effective in restoring the appearance of wooden surfaces by reducing the visibility of scratches and imperfections.
Delta Kits is an online site that offer information on windshield scratch repair. You can get information on repairing yourself instead of taking to a repair shop.
It is best to fix it with a wax specifically for glass with a scratch remover in it.