What is 303 anyway?

Everyone loves 303 Aerospace protectant.

But why?

Their literature and website uses a lot of space telling you what 303 isn’t. No silicone. No petrolium distillates.

And they tell you how bad the competing products are.

But they don’t tell you what 303 is, or how it works, or why it won’t cause problems.

They rely heavily on testimonials.

Generally these are all warning signs of “snake oil”.

Any yet most plastic boat manufacturers, and drysuit makers recommend the stuff. Why?

Where is the real technical information on 303?

why not?
Betcha never saw a UV degraded snake …

mintjulep — agree.
I asked myself the exact same question, and could not have posted it any better than you just did. I think it is phooey. I put some on my plastic kayak, 303 out of the bottle, wiped it in real good about three weeks ago, and took that yak out to the pond this past weekend, and yes, could see oily, fine wavy texture in the water near the sides of the hull… ie. the famous 303 was basically just washing off the boat. So this tells me that it is not totally waterproof, and whatever it is, does not seem to get into the molecules of the plastic very well. Perhaps it is a UV protectant on an obbject that does not get wet in lakes or rain, but … even that I question. Many commonly used products… Rainex, for instance for car windows (and works well on shower doors too), is basically alcohol. Could use rubbing alcohol at 0.99 cents per bottle too, or so I have read (I did not try this). But good old 303, nary a mention of the ingredients. Wonder if I drank a couple swigs and called Poison Control if the old 303 company would then have to fess up and tell us the make-up of it. Also, please link it here if there is a 303 website. Good post.

303 web site


– Last Updated: May-08-06 2:11 PM EST –

"if there is a 303 website"

I guess people haven't heard of "Google".


Rain X
Rain X at least I understand how it works. You wipe it on and it leaves a film of something (probably PVA) that fills in the tiny holes in the glass and makes a nice smooth surface.

Thanks for the link, mintjulep
Saves everyone from having to Google the site.

Askjeezes.com does not have any answers either. I see some sites that say it is SPF 40. Wonder if I can use it on my skin? Better yet, since 303 is greatly expensive, would be to use Coppertone on the kayak.

All I know is…
Top Boat: 1997


Bottom Boat: 2003

Photo taken when bottom boat had been in the water once- Top boat has seen frequent applications of 303 and well used. Gotta Love that kind of Snake Oil!


McGuire’s vinyl protectant
Check spelling. They make car wax and stuff too but their vinyl protectant works rather well too. I’ve used it on my canoe a few times and like it. Haven’t really compared with 303 as far as which last longer.


– Last Updated: May-08-06 4:09 PM EST –

"Rain X at least I understand how it works"

Well, one can also surmize how 303 might work: just like sun screen lotion.

Why is 303 any more mysterious than sun screen lotion?

Anyway, I suspect that Rain X adds a persistant surfactant ("sheeting agent") to the glass. I doubt it "fills in any holes".

A surfactant would be opposite to what Rain X does. A surfactant reduces surface tension and allows sheeting.

Rain X promotes beading.

Along those lines, my previous guess that Rain X is PVA appears to be incorrect, as PVA would act as a surfactant.

The mistery of 303 is the claim to do so many good things on so many different materials. I’ll admit that it makes things pretty. I want to know how.

For clues…
… look toward sunscreen products. They do list ingredients. From there remove botanicals like aloe and fragrance that would be a waste of $ on palstics and fabrics, maybe alter the remaining carriers to better interact with the surface layer of plastics than skin (technically, skin could be classed as a plastic)…

Just idle speculation…

303 for latex - Armorall for others
You’re right that 303 tells you what it doesn’t have but not much else. Kokatat recommends it for their latex seals because I guess silicone is not good for latex. They also tell you that sunscreen is not good for the latex seals. So, I use it on the seals.

But to shine your boat or paddle or varished wood kayak etc. I use whatever is on sale like Armorall which is about 1/3 the price. They all have UV filters.

Sili or not sili?
Jaybabina wrote:

Kokatat recommends it for their latex seals because I guess silicone is not good for latex.

True, Kokatat sez: “Latex gaskets need to be treated every 4–6 weeks to prevent drying and cracking. Kokatat recommends 303 Protectant …”


And yet Palm, no slouch when it comes to drysuits, suggests: “To keep your latex seals in good condition, regularly apply a silicone-based rubber conditioner.”


So here we have two major mfr’s of drysuits which utilize latex gaskets giving very specific and OPPOSING advice on how to properly care for the latex. Notice, however, that the only party who claims outright that silicone-based protectants are detrimental to latex is the maker of a competing product: 303.

C’mon, there must be a chemical engineer or polymeric wonk among our ranks, to give his or her thoughts on the subject!

No contradiction.

– Last Updated: May-08-06 6:21 PM EST –

"So here we have two major mfr's of drysuits which utilize latex gaskets giving very specific and OPPOSING advice on how to properly care for the latex."

Not "opposing", just different, advice.

Both could very well be reasonable treatments.

Where does 303 say silicone is "detrimental" to latex?


I suspect that silicone doesn't provide much UV protection.

A little more searching
I looked at the Goodyear, Goodrich, Yokohama, and Michelin tire web sites.

None are recommending 303. Only Michelin recommends any type of treatment - their own.

To be fair, the Michelin treatment product sounds similar to 303 - UV protection, anti-ozone, not petrolium distilates.


The Michelin stuff seems to be cheaper than 303, so it might be worth a trip to the local auto parts store to see if they have any if you are in need of something.

hey gnomon

– Last Updated: May-08-06 10:26 PM EST –

Thanks for posting the picture. Not only shows the benefits of the 303, your rack gave me a thought on the way I'm going to hang my kayaks off the side of my shed.

303 also recommended by Watershed dry
bags. Watershed recommends it for use on the zip lock type seal which normally wouldn’t be exposed to UV. However, it does lubricate the seal and makes it more supple - much easier to open and close than untreated. I would presume that at least some of the manufacturers that recommend 303 and other products have done some testing of the product they are recommending. Also, rubber bands will deteriorate without exposure to UV from sunlight, much like latex gaskets will do if hung in a dark closet for years. Apparently there are other things whcih will also cause latex to degrade (ozone?) and the use of 303 may help to extend their life. Seems to me like a small price to pay to possibly extend the life of $100 worth of latex gaskets on a drysuit and $150 worth of VCP hatch covers. I’m much less concerned about treating my poly and composite boats because they are stored under cover. However, I treat all of my rubber bands every 4-6 weeks. I just don’t want to chance that they might fail early :slight_smile:


Live is better than Google
Found this interesting site when searching using http://www.live.com:


While it had some information on 303 I found the other stuff equally as interesting. Google is just not what it used to be now that Microsoft has built their search capabilities. Also http://ideas.live.com is a pretty cool place for new services.

This is interesting the composition is
listed as Proprietary …