3M Marine Adhesive Sealant 4000 UV (05280), Medium Strength Flexible Waterproof Adhesive Sealant for Boats and RVs, UV Resistant, Cures in 24 Hours, White, 3 fl oz Tube

Great product! Works great! Highly recommend!

Works great. It 3m. Nothing more to say. Don't get it on your hands! It aint coming off. Wear gloves.

Great sealant.

Excellent quality and better than marine silicone. Returned this for the black color version of this same product…so bc abbot comment on white color Pantone…but black option fired perfect and sealed up my boat project.

I bought this product for sealing the lens to a Bomar hatch frame on our sailboat. It worked great and provided good adhesion to both the plastic lens and the metal frame. I then decided to use it when replacing a portlight window. It seems to have worked very well there as well. It seemed to be easier to work with than a competitor's product that I used on a previous portlight. Time will tell as to how well it holds up and remains watertight. I especially liked that the instructions on the tube said that cleanup can be done with isopropyl alcohol. As cheap as isopropyl alcohol is, I was excited to use a cleanup agent that worked well and that I didn't have to feel that I needed to use sparingly due to cost. the alcohol cleaned up the sealant very well. The only negative that I can say is that it is fast cure (as the label says). It was almost too fast cure when applied to the lens. I left it set a bit too long (20-30 minutes) before dressing up the seam and it was difficult to smooth out-- my fault for waiting too long. As long as you clean up the seam and smooth it out relatively soon, it should work great.

Why did you pick this product vs others?:Top quality marine adhesive just very pricey but it definitely works and you can do without it!

Moving to a new house, we unknowingly let a vinyl lined hot tub (Softub) sit in the summer air upside down for three months. BIG mistake. This resulted in several rips and tears (including one 2 feet by 6 inches!) in the inverted sagging of the long-water-dependant vinyl. We thought our hot tub was a goner. Tried numerous hot tub rip repair kits, and none of them worked well enough for this major repair job. The hot tub was aging and had served us well for nearly a decade, so we didn't want to purchase a complete replacement liner because of the price - either fix it or toss it.Vinyl patches provided were strong enough, but none of the vinyl patch kit adhesives were able to really withstand the stresses of a full 300 gallon water load on the stretchable vinyl. We made all repairs while tub was empty so as to obtain the best seal. In addition to vinyl-specific glues and patch kit adhesives, we tried vinyl contact cement, shower pan liner adhesive, and every single type of PVC/vinyl glue at the local home improvement store. Not even Loctite plastic bonder would hold once the hot tub was full and chlorine was added to the water.As a last resort, we decided to give this "below the waterline" "hull repair" "permanently flexible" sealant a try - and WOW! it sticks to everything. We gave it a good cure of several days (this was outdoors in winter, so took a bit longer). We used this to adhere the vinyl patches to the tub' vinyl liner, to each other, and to feather around the edges so as to prevent bathers from tearing up the sides or water working the sides loose from the jets.2 months in to this repair, from which no other product/system/glue previously lasted longer than a week.Much impressed by the miracles of modern petroleum strength commercial chemical derivatives - nicely done 3M!

This is THE product to use for marine applications when you don't want a permanent bond. The issue for me is, it's quite expensive and I only tend to use a fairly small amount at a time for repairs (e.g., installing a replacement stanchion). They tell you that you need to use it within one week of opening. This is only true if you want to dispense it through the nozzle. What I do for small jobs is punch a small hole in the side (I use a nail set or a nail), squeeze a little out using a caulking gun, and spread it with my finger (in a nitrile glove), then slap some tape over the hole. I've now been using one tube of a year on 6 small jobs, and I expect to do more.