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303® Aerospace Protectant™ on Fiberglass

303® For Fiberglass...Never Buff or Wax Again! 
303® Products on Fiberglass

Like vinyl, gelcoat fiberglass (polyester resin) is a UV sensitive plastic. Though manufacturers add UV stabilizers to vinyl and gelcoat fiberglass in the manufacturing process, these protective agents weaken over time and must be replenished if continuing UV protection is desired (See volume 4). Colored gelcoat fiberglass is particularly sensitive to UV degradation and 303® Aerospace Protectant™ is by far the easiest way to make colored fiberglass look like new again and to keep it that way. Nothing else is even close.

303® Aerospace Protectant™ works by penetrating to restore a like-new color and gloss. Spray on enough 303® Product to thoroughly wet the surface (303® Product goes farther if it's sprayed on and then rubbed around and in). Wipe away excess with soft, absorbent cloth. Wipe until completely dry, changing cloths as cloths become damp. Unlike wax, 303® Product is not left to dry before it is wiped off. If 303® Product has dried on the surface, it is easily removed by spraying the area with more 303® Product, then wiping dry.

For best results, apply 303® Product out of direct sunlight so fiberglass surface is not overly warm. A hot surface causes 303® Product to evaporate before it can do its job.


Reapply by spraying 303® Product on the surface and wiping dry with a soft, absorbent cloth...very much like dusting furniture and just as easy! For trailered boats, a convenient time to reapply is after trailering, just before toweling it dry. Mist it lightly first with 303® Product, then towel dry...takes an extra 30-40 seconds. This is an excellent way to keep up the UV screen and totally prevent UV caused slow-fade. Plus dirt, road grime, and 60 mile-an-hour bugs will not stick to a 303®'d surface (you'll love it!).

When to Reapply 
303® Product is water repellent (beads water). When the water repellency begins to diminish, reapply. Or if you think it may be time to reapply, but don't know for sure, do a small spot with 303®. If any of the color or luster comes back, reapply. Usually, a simple spray on/wipe off reapplication every 30 to 80 days of exposure is sufficient.

Does 303® Product Always Work?

303® Product always works unless there is something on the surface keeping 303® Product away from the fiberglass...teflon, silicone, polymer sealants, or fresh wax. If the surface has been freshly waxed, it is not necessary to remove the wax. Just wait a few weeks and try again. Wax does not last long enough to warrant the effort required to remove it.

About 2% of the time pre-buffing (compounding) is required. When required, be sure to use a rubbing compound that does not leave a coating or sealant. Use pure rubbing compound with only the finest abrasive.

Older Surfaces

Even after a few years without care, it may be unnecessary to compound before using 303®. Use 303® to find out for sure.

First apply 303® normally. If this does not restore the like-new color and gloss typical with 303®, try this: In the shade (or just before dark), spray a basketball-size spot with 303®. Rub it in and spray again to make sure the spot is thoroughly wet with 303®. Let set for a few hours or overnight. Spray the spot again with 303® and wipe dry. This is often all it takes to make gelcoat look like new again without compounding.