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Marine 31 Mildew Stain Remover 32 oz.

Marine 31 Mildew Stain Remover 32 oz.
Remove stubborn mildew stains – FAST!

Marine 31 Mildew Stain Remover quickly and safely removes stubborn mildew stains on virtually all marine surfaces, including vinyl seat cushions, rubber fenders, fiberglass, gel coat, canopies, and more! Marine 31 Mildew Stain Remover forgoes volatile cleaners and instead relies on smart chemistry; even the most severe mildew stains are no match for the incredible cleaning power of Marine 31 Mildew Stain Remover.

Marine 31 Mildew Stain Remover is the best boat mildew cleaner available!If you’re a boater, chances are you’ve dealt with the seemingly lasting results of 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 stain cleaners. Fortunately for you, we’ve compared Marine 31 Mildew Stain Remover against other marine stain removing cleaners and have found that it removes mildew stains faster, with less effort.

Not all marine mildew stain removers are created equal! Most over-the-counter marine mildew stain cleaners rely on heavy concentrations of bleach and other volatile chemicals that actually cause more harm than good. But Marine 31 Mildew Stain Remover removes stubborn mildew stains without discoloring, dulling, or drying out vinyl surfaces.

Best of all, it still retains the powerful cleaning ability to remove mildew stains – FAST and in the convenience of a spray bottle. To use, spray and allow to dwell for up to three minutes before thoroughly washing away. You can use a brush or microfiber towel to agitate the surface. Once done you can say goodbye to the mildew stains! You can safely use Marine 31 Mildew Stain Remover on vinyl cushions and chairs, rubber fenders, fiberglass, canopies and boat tops. But don't forget, Marine 31 Mildew Stain Remover can also be used inside the home as well! Use it to clean and remove mildew stains from tile, grout, showers and bathtubs, counters and sinks.

Use Marine 31 Mildew Stain Remover on:
  • Vinyl cushions and chairs
  • Rubber fenders
  • Fiberglass
  • Gel coat
  • Canopies
  • Boat tops
Marine 31 Mildew Stain Remover works wonders for household cleaning as well! Use this professional strength formula to clean tile, grout, showers, bathtubs, counters, and sinks.

Marine 31 Mildew Stain Remover works FAST!Directions:
  1. Spray directly onto surface and allow 1-3 minutes for penetration.
  2. If necessary, agitate surface with a brush or terrycloth towel.
  3. For stubborn stains, allow cleaner to penetrate for 5 minutes before agitating.
  4. Thoroughly rinse and dry surface.
  5. Follow with Marine 31 Mildew Stain Guard to protect treated surfaces.
32 oz.

Made in USA

Federal regulations prohibit the shipment of this products by air, UPS 3 Day, UPS 2, or US Mail. This item is shipped by UPS Ground only. Sorry but no APO or FPO addresses.

Marine 31 Mildew Stain Remover 32 oz.
Item #: M31-371
Our Price: $29.99, 4/$89.97
Availability: Usually ships the same business day

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Product Reviews

57 Reviews
93% (53)
5% (3)
0% (0)
0% (0)
2% (1)
98% Recommend this product (56 of 57 responses)
Hayward, WI
Great Product!
Gets all the mildew stains off everything and cleans up other stains too.
Lake Oconee GA
Awesome Product
Searched for years for a boat cleaner that would clean mildew up for of our boat. This product did it!!!!
Sea Bright, NJ
This product really does work as advertised!!!
I have had small mildew spots on my bench seat on my flybridge for many years, which I have tried everything to remove. Nothing has truly worked until I tried Marine31 Mildew Stain Remover. Within minutes, the mildew was breaking up and easily wiped away with a terry cloth towel. Certain areas needed to be treated twice.
ProsEasy to use and it works!
ConsIt smells like it contains bleach, which it obviously does. It took the color out of my sweatshirt and pants while using the product. Be careful using it.
Great product!
My husband and I are meticulously clean when caring for our boat. After a winter of storage when it gets some mildew on the upholstery, this product eliminates it completely.
This is the BEST mildew remove product I have ever used!!!!! I have been boating for over 40 years and NEVER found a product that works this well. It is so easy to use no scrubbing at all.I live in Fla, where mold is problem Marine 31 is the solution!!!!!
ConsI cannot find marine 31 at any local merchants. Buying it on line is the only way I could purchases it.
Cudjoe Key Florida
Mold on pontoon seats
We had mold all over our pontoon seats that other products didn’t touch. Marine 31 removed most of the mold within 5 minutes. My husband found brushing it on with a paint brush had more control of the product so it wouldn’t spray on the seams. We really are happy with the results and have shared it with our friends.
New York
Marine 31 Mildew Remover
I have tried several other products over the years with limited success. The ones that worked still required repeated applications and a lot of scrubbing. I could literally see the mildew stains disappear moments after I sprayed the area.
It worked great
I used Marine on my 1991Mustang GT convertible top and it is a brilliant white again. I should have taken a before and after picture, the difference was amazing. Just prayed it on and rinsed it off. It was done in a short time. I would highly recommend Marine 31.
ProsWorks as advertised
Amazing Product
I wish I took a before and after white boat seats were loaded with mildew....used Marine 31 and let it sit. Didn't even have to scrub...this stuff works all by itself. I gonna buy more for my other boat and golf club seats.
Bel Air, MD
Return customer
We've tried everything to get rid of the mildew on our vinyl pool lounge chairs. I found this online and read all about the great ratings so I decided why not give it a try.
It truly is amazing! It completely removed all the mildew and kept is away! We have 8 lounge chairs and the smaller bottle cleaned 6. Reordered more but bought the 32 oz to last through the summer.
Great product and does exactly what it says. Again, I've tried EVERYTHING for the past 3 years and I will no longer waste my time on alternatives. Marine 31 will be all I use each season!
trinity, alabama
This product does what it says it will do.
I will purchase again
Brandon Fl
Better than expected
I bought a bottle with doing some research and hoping for the best. I was so happy that the product worked as advertised and turned my seats from basically nasty to DAMN CLEAN. I. impressed.
Mobile, Alabama
Loved this product
It worked beautifully without fuss... boat seats look brand new. Had doubts they would clean up but this did the trick.
ConsShipping cost & It took to long to arrive... I am Amazon spoiled 😜
Our older pontoon looks like new.
Indianapolis, Indiana
It works!
We thought we had our boat seats pretty clean until using Marine 31 - they're now next level clean. Great stuff so far!
Nokomis, Fla
Marine 31 is the best product EVER for removing mildew and ALL stains from marine vinyl. Easy to use even; literally spray on, let it work (some spots take longer than others), and wipe it off. I used it in the entire cockpit of my 2001 boat, and it doesn’t look like a used boat at all!! Love this product!!
Unbelievable product cleaned all seats like new in 50 minutes on my 24ft pontoon!
Cicero In.
Great cleaner
Marine 31 mildew cleaner works best. Little bit goes long way. Cuts the time .
Balaton, MN
A great product.
It was absolutely amazing how well this cleaned our pontoon seats. They almost looked new.
New Hampshire
It works!!
I’ve tried everything to get rid of those gray mold stains on the boat. This is the only thing that worked!
Chesapeake City, MD
Good, but not as great as I had hoped.
I was hoping to eliminate the black dots and yellow/orange stains on our pontoon seats. While this product definitely made the seats cleaner, it really did nothing for those issues. We wound up having to use a wipe on paint product to cover the stains.
Pros- Partially cleaned seats - Fair price
Cons- Didn't eliminate spots - Didn't eliminate certain stains
Simply the best
Unlike other mildew products, this one really works.
ProsCleans real problem areas if you follow directions.
ConsMust use gloves! Protect your hands.
This one works!!
I have tried them all. This is the ONLY product that works.
Naples, Florida
Saved us thousands in replacement costs!
We have outdoor furniture made by Ethos. They are outdoor wicker and cream colored “marine leather”. After 5 years of being in the lanai they were starting to mildew even though we cleaned as suggested by the manufacturer. Heartbroken we had almost decided to replace them when I did a little searching on the internet. I purchased this product with the mindset of having to replace anyway, so no harm. I literally sprayed and walked off to get a cloth. By the time I came back, less than 2 minutes, most of the mildew was running down the sides. I simply wiped it off!!!! There were 2 areas on 2 chairs that needed extra applications but EVERY SINGLE PIECE LOOKS BRAND NEW! I am heartbroken I didn’t think to take a before photo. You have a devoted fan and forever customer! (I purchased all the other products that go with this too!)
ProsEffective!!!! It really works!
ConsCan be a little harsh smelling, so use in a well ventilated area.
New Port Richey, FL
works great
best product on the market for mildew removal
Conslittle pricey
Naples, FL
worked like a champ
It was like night and day. I was very skeptical after seeing a video of how fast and well it worked. Tested it out on one section after i took the covers off the boat. Was so easy, i didn't have to agitate the area at all. Would highly recommend this for anyone who has those mildew spots. Going to buy the mildew guard. Looking at other products they have.
Girard, Ga
Best yet!
I have tried all sorts of cleaners to remove mildew from my boat seats. Marine 31 is by far the best I have ever used!!
Okeechobee, Fl
Works great with very little effort!!
Best ever used!
Utica, New York
Amazing Product! I am a believer!
I remained skeptical even after watching many You Tube videos . But I am a believer now! I have a 1996 pontoon boat with seats that are in great condition but were covered with the unsightly black mildew stains.
After just 1 application of Marine 31 Mildew remover the mildew was gone!
Dana Point
Awesome Product!!!!!
I just used Marine 31 on my Boston Whaler backseat cushions that had spots that I could not get rid of. They were small dark spots and I figured I would have to live with them until I used Marine 31. I wish I took a before picture but I was too excited to try this stuff out and I don’t think I was a true believer until now.

Thank You!!!!