303 Marine Fabric Guard (1 Gallon)

We apply this every year to the canvas cockpit enclosure of our boat. By sealing the fabric, we keep the cockpit dry, but also slow down the development of mold and stains on the canvas.

I’ve tried several brands of products for waterproofing. This one isn’t cheap but it works, though it smells very much like it contains the same stuff as Fabsil.

This works really great one bottle was pretty for my little boat cover and even brought some color back to cover. Was streak free and no greasiness to it at all.

Wow, this stuff works. We sprayed the whole gallon on our boat canopy and not one drop of rain came into the helm- dry as a bone. I plan on spraying yearly or as needed. You pay a little more for this product but it works. We bought a gallon garden sprayer and it worked like a charm.

Our boat cover had gotten to the point where rain just sat in puddles across the top instead of running off, worried it was slowly soaking through and encouraging mildew underneath during storage. Grabbed the gallon size specifically to treat the whole cover since it's a big piece of fabric and I didn't want to run out halfway through. Sprayed it on while the cover was laid out flat and fully dry, made sure to get even coverage across the whole surface including the seams where water tends to sit longest. Let it cure overnight before covering the boat back up like the instructions suggested. First real rain after treating it made the difference obvious, water beads right up and rolls off the sides instead of pooling on top waiting to soak in. No more coming out to check on standing water after a storm, which was my main worry with our old faded treatment. Cover still feels normal, not stiff or crunchy like I was a little worried a fabric treatment might leave it, folds and stores the same as before. Only complaint is you really do need calm, dry weather to apply it properly, had to wait a few days for the right window rather then just doing it whenever I had free time. Great fix for a cover that was starting to soak through instead of shedding water like it should. Applys easy but there is definitly some odor so do it in the wind if you can. Not sure its safe to huff in.

Very happy with how this is performing. It has been about 6 weeks since I applied it to my Sunbrella fabric on my outdoor couch. These pads would get dirty within 24 hours of laundering them and you simply could not clean them without taking them off of the foam, spotting them, and laundering them. A major pain. Now after 6 weeks they are still perfectly clean. Anything I get on them brushes off. My advice however is to not do what I did. I sprayed everything down and had about 1/4 gallon left and decided to put a second coat on rather than toss it or store it till next year. Don't do that. It left an irregular pattern on them, it is barely visible, but prior to that they were literally perfect. I used a pump sprayer that you would typically use to spray weeds and that did a nice job. Also, avoid overspray on your patio, now the water beads up there and not other places, so it is a bit weird when wet. I have not been covering the furniture at all and all the random outdoor stuff that blows around or animals bring in has not been a problem, nor has my 13 year old son's penchant for spilling food on them. I expect to launder them next spring and put a new coat on, but maybe I won't need to.

This product is nothing short of amazing! I purchased a used boat that has 2 canvas covers. The covers are in good condition but leaked a significant amount of water. This product saved my boat covers! I'm so happy I spent the money and went with this brand!!! I was considering a cheaper brand, but 2 things made me decide to order this one: the videos that others posted that showed them pouring water on the surface (that's exactly how it works!) and the fact that my local marina sells only this brand (for a whopping $168!) I didn't skimp - I first washed the entire canvas with the recommended 303 Multi-Surface Cleaner, rinsed well and dried overnight. I didn't actually use a garden sprayer. I used a heavy-duty industrial spray bottle (to control the application and the "overspray") and thoroughly sprayed it on in sections. It was a very hot, sunny day, so it dried very quickly. (I left the canvas attached to the boat for the application, so I was very careful to mask off the surfaces I didn't want sprayed!) I left it to dry overnight. The next morning, I did my water test by pouring a large jug of water over it. It worked just like the videos! The water beads up and rolls right off!!! I'm SO happy with this stuff, I've now used it on my cheap, not-waterproof outdoor patio cushions and toss pillows! The money I've saved just by not having to replace outdoor cushions would have justified the cost of this product, but it has also saved me a few thousand in replacing my boat covers! Highly recommended!