I bought a bunch of the protec stuff after reading the recommendations here. It is okay, but I found it wasnt nearly as good as my starbrite marine polish w/PTFE. That stuff removes black marks, residue from the boat cover, road tar……anything that doesnt wash off comes off with this polish and leaves the glass smooth. On a molecular level of sealing the glass and whatever protec is supposed to do, I dont have a clue if they are comparable but I only used it one time and went back to the starbrite. I still use meguiars marine wax too, but only once or twice a year.
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