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Marine 31 Mildew Stain Guard

Marine 31 Mildew Stain Guard
Prevents mildew stain growth

Marine 31 Mildew Stain Guard is the solution to a common problem that plagues all boaters – mold and mildew stains on vinyl surfaces. This high-tech vinyl sealant forms a clear coating that protects against UV rays, body oils, salt, and most importantly, stubborn stains caused by mold and mildew. Treated surfaces will retain their flexibility while being well protected against the damaging effects of nature.

If you’re a boater, chances are you’ve dealt with stubborn mildew stains on vinyl cushions. If you’re reading this product description, chances are you’ve been less than satisfied with the performance of other so-called marine mildew protectants. Fortunately for you, we’ve dealt with every type of stain caused by mold and mildew there is, and developed a product to stop it in its tracks – Marine 31 Mildew Stain Guard.

Marine 31 Mildew Stain Guard protects against mold and mildew stains!
Spray and wipe - it's that easy!
Marine 31 Mildew Stain Guard is far more than a vinyl protectant. This high-tech vinyl sealant actually forms a clear coating over treated surfaces, creating an impenetrable barrier of protection that prevents stains caused by mold and mildew. In addition to providing durable protection against mold and mildew staining, treated surfaces will be noticeably easier to clean. Regular maintenance can be performed with a dampened microfiber towel.

Marine 31 Mildew Stain Guard allows you to spend more time enjoying your boat, and less time performing laborious cleaning tasks. Application is as simple as spraying on and wiping off. It only takes seconds to apply, but the protection provided lasts months! The clear coating resists UV-induced fading and discoloration as well, making it the best marine vinyl protectant the boating world has ever seen!

  1. Ensure surface is clean and out of direct sunlight.
  2. If mildew stains are already present, use Marine 31 Mildew Stain Remover first.
  3. Spray product directly onto microfiber or terrycloth towel.
  4. Gently massage into surface, making circular, overlapping motions.
  5. Wait 2 minutes then lightly buff with a clean, dry microfiber towel.
  6. Apply a second coat 10 minutes later to ensure even coverage.
20 oz.

Made in USA

Marine 31 products are harbor safe and eco friendly!

Marine 31 Mildew Stain Guard
Item #: M31-450
Our Price: $29.99
Availability: Usually ships the same business day
Our Price:$75.94Sale Price:$54.99

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Product Reviews

Review Summary
12 Reviews
83% (10)
17% (2)
0% (0)
0% (0)
0% (0)
100% Recommend this product (12 of 12 responses)
Works great
Nice finish... Wipe down with microfiber cloth
Maitland, FL 32751
great for keeping the mildew away in our humid air ( Florida)
Great for guarding vinyl from mildew growth return after all that scrubbing.
Prosnice shine on the vinyl
Central Wisconsin
Made my boat seats look like new
The vinyl on my 19 year old pontoon boat looks new again.
ProsEasy to apply.
Stuart, FL
Great Product
It’s a great product, unfortunately I meant to order the Mildew ‘REMOVER’.
Atlanta GA
Solid protectant
Longevity is still questionable as I’ve just received this product a few weeks ago but I can say it applied easily and left no greasy sticky mess after applying. I like that it subtly seems to deepen/enhance the colors of the vinyl. My seats are light grey and white so it is very subtle but a good result. Upon first wipe down after application having only been out on the water once since I’ve applied it it does seem to wipe down a bit easier than before. I’ll have to wait and see how it holds up. It mentions applying monthly which seems appropriate assuming you are using your boat regularly so I don’t really understand the reviews that say after six months or more it’s not that effective, makes sense to me that it wouldn’t be.
ProsEasy application and nice non-greasy or sticky finish.
ConsNone thus far
Wish I knew about this stuff a long time ago!
This stuff really works. I actually used it by accident, thinking I was applying the Vinyl Protectant. I coated my pontoon seats prior to putting the boat up for the winter. When I uncovered the boat this spring there was absolutely no mildew or black spots. That's a first! This product is now a regular part of my cleaning routine. But I am having to clean my boat MUCH less than I've had to in the past. Great Product and I highly recommend it!
Weeki Wachee, FL
Works As Advertised
I have purchased both Marine 31 Mildew Remover and Mildew Guard twice now.

The Guard works pretty well, and the Remover woks better than anything I’ve ever used!

Our ‘toon is in the water at the dock 24/7/365, come rain, blazing sun and heat, or whatever, so mildew USED to be quite a problem.

I’ll be buying this stuff as long as we have boats, and I recommend it to everyone I know that owns a boat.
Punta Gorda
It works!
Best product I have ever used to keep mildew at bay!
Middle Tennessee
Great product!
Works as advertised. Has kept mold off my pontoon boat seats.
Ravenna, Ohio
Great product
This product applies very nice and leaves the vinyl looking great. My boat is in storage for the winter so I won't know how it performs until next spring.
Greenville, South Carolina
Remains to be Seen
Like this product! Puts a coating over the seat to keep it from getting mildew & helps keep it clean & shiny. I will know more when i check it next year. Only been 2 weeks & looks like it was just cleaned.
Tampa, FL
Like a vinyl protectant on steroids!
I used to apply a protectant every other weekend but now I just use Marine 31 mildew guard because it lasts more than twice as long. It actually makes water bead up which is really cool. The vinyl seats on my boat are also much easier to dry.
ProsSuper long lasting and easy to use
ConsA little pricey but for as long as it lasts you can't beat it.