303 on Glass Boats???

Recently saw someone mention that they used 303 on his glass boat for UV protection.

I know it is recommended for plastic boats but that was the only time I had ever heard of it being used on glass.

Do you use it on yours? Is it advisable to keep it off the bungees?



Use it on my glass boat all the time. Try not to get it on the bungies. After I put it on I wipe again with a clean cloth. Gets really slippery.


303 works great on fiberglass. Most people spray it on and rub it in with a saturated cloth, wait a few minutes and then wipe off the extra. The 303 website says to let it sit for considerably longer before wiping off the excess, like overnight (but not out in the dew/rain/mist). You can also use an electric buffer to work it into the gelcoat. Mostly, just getting the gelcoat saturated and then wiping off the excess works for me on fiberglass.

Yes, I’ve used it for many years.
Because it fools me into thinking that the gel coat scratches aren’t as bad as they really are.


use it on your fiberglass boat
right before you show it to a prospective buyer!


Or spray it with poly enough ahead of
time for it to dry.

303 is not for glass but
a glasfiber reinforced plastic boat is made from glass AND plastic (polyester/vinyl ester/epoxy), and for that 303 works well in my experience. Better and easier than wax at least.

One thing to remember is to clean even
more thoroughly if you break the “glass” and have to do a repair. Resins must have a very clean surface in order to stick.