is safe to use on glass cooktops and acrylic surfaces without scratching. It is no more abrasive than a final finishing compound used to polish fiberglass. It also won't make the gel coat porous as gelcoat is already porous. I used it on my boat for 4-years for deck surfaces that are not non-skid with excellent results. It leaves a nice glossy shine it easily removes water/rust/soot stains.
My boat is 31 years old and has the original gelcoat which has never been painted and looks like it came right out the mold. I have had people come to me ask ask me what kind of boat I have. When I tell them it a 1979 Pearson, they go wow!, looks like it's brand new.
If you are worried about using it, try it on a small area first. You can follow it up with A polishing/final finishing compound, like Finesse II to really yield a high gloss.
Softscrub is MUCH better than using a scotchbrite pad to remove stains on gelcoat. Scotchbrite will scratch it.
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