5200 Marine Sealant Adhesive Fast Cure - Permanent, Watertight Bonding and Sealing - UV Resistant, Above & Below Waterline- for Boats, Hulls, Decks & RVs,Pond Sealant 3oz (1Pack Black)

I had 15 years of experience with 3M's 5200 Marine sealant while I cruised (on a sailboat) the US East coast and the Bahamas. Folks would use it to caulk, being unaware that they were PERMANENTLY bonding whatever they were caulking to keep water out. I, knowing the nature of the stuff, used actual caulk for those jobs. On the other hand... (Well, neither, actually, if you wear the encouraged latex gloves, or in this case, the included condom for midgets, or, as you might prefer, a roll-on guard against your finger getting this stuff on it.) That 5200 was a very fine permanent adhesive - and breathtakingly expensive by comparison to Tylove's product. Consultation with the makers have confirmed my experience (see pix): Unlike many others, this does just fine in adhering plastics. In my case, it was another of Amazon's fine products which, after 5 years of heavy use, had the mechanical fastenings (latching parts) fail, resulting in our vacuum's dust cup and power-transfer nozzle becoming separate entities. Enter this goo. The two plastics involved are ABS and Polypropylene. The stick together like - well - 5200! I'm ashore, permanently (no, not stuck with 5200!), now, and love that this very successfully - and, now that it's no longer mere clip latching - permanently restored my lightweight cordless vac. I've gotten better at its tidy use; the neater pix are of the second unit having EXACTLY the same failure... I'm stuck on this stuff ☺ Just a note, however: This stuff isn't instant cure - which is very good for alignment and cleanup purposes. But it DOES cure with ANY air-touch. Which results in a plug of cured stuff when you go to use it again later, presuming you've not used up the entire tube. But all isn't lost, at least if there was a tight seal - or perhaps you used the nozzle, and capped it by running an appropriately sized metal screw (so the end was sealed). You'll still have some solidified stuff. But the plastic in their tube and the nozzle aren't going to stick. When I lived on a boat and had full caulking gun (squeeze the trigger and a plate pushes on the bottom of the tube) canisters of the same stuff, I'd do that - and then unscrew the now-solid nozzle, unscrew the metal screw, and use that screw, screwed into the other end, to pull out the plug. The same trick will work on this tube and nozzle - though you might have to rock the tube end a bit to persuade that plug to come out, presuming it's hardened to that depth. That's just a heads-up. I only used the cap, but my eyeball has a #10 or #12 as the right sized metal screw.

This stuff is AMAZING!! it isn't epoxy, but it hardens very quickly, sticks veraciously to everything (even underwater) and bonds AND FILLS plastic and PVC PERMANENTLY. Wear gloves because this stuff is impossible to get off of your shin WITH ANYTHING. It comes in a single tube with the consistency of toothpaste and hardens like steel within moments of applying it (above or below water). Unfortunately, the tube's orifive will seal over after use, but can be removed with a blade and the paste remains soft inside. I had purchased pool putty (water grade) to fix an underwater PVC structure that was cracked, and the 2-part putty wouldn't adhere to the PVC. This paste applies easily to anything and is solid within 45 minutes. Water DOES NOT dilute it at all, nor does soap, alcohol, or acetone, SO WEAR PLASTIC GLOVES. This stuff can make a mess easily that is near impossible to clean up or get off of your hands. But it it the best one part universal bonding paste I have ever used!!

This is quite an amazing sealant. I have used a lot of different things through the years working in the automotive and boat fields, and this stuff sticks amazingly well. I did clean the aluminum down till it was bare with a wire wheel before applying, and then cleaned the surface with alcohol. My boat had a spot where somebody had a battery that ate about 10 pin holes through the aluminum. It is completely sealed, 100% watertight now.

Good sealant but small tubes overall expensive for the quantity

I used the 3oz Marine Adhesive Sealant 5200 to seal a panel on our aluminum trailer, and it worked great. I was looking for something that would give me better adhesion than just regular silicone, and this definitely delivered. The sealant is thicker and more durable, so it felt like I was getting a permanent, watertight bond, which gave me peace of mind knowing the patch panel is securely sealed. A little goes a long way with this stuff, so you don’t need to use much. The black color blends well with the trailer, but I noticed it also comes in white, which could be useful depending on your project. While it’s on the higher end price-wise, it’s totally worth it to avoid the alternative—water intrusion is definitely not something you want to risk. Overall, I’m confident that this sealant will hold up over time, and I highly recommend it if you’re looking for a strong, long-lasting seal. It’s perfect for outdoor or marine applications where you need something tough and reliable.

This is just expensive regular silicone sealer, not even close to the original 3M 5200 polyurethane. DO NOT use it below the waterline as they suggest. Silicone is not made for constant immersion and using this on a through-hull or other underwater hardware will compromise the integrity and safety of your vessle! This is totally false advertising. Sure,it's fine for RV's, and above the waterline general sealer, but it won't give the adhesion strength, longevity, or sealing properties a polyurethane product will. And beware of the misleading pics: what looks to be a 3oz tube is actually a 1oz. But the price looks like it! If I could give this zero stars I would. Caveat Emptor!

Tip came top part dried out. Poke a nail or something small to discard that little bit then squeeze and work normally. Good results. Used for Kreepy Krauly repair for pool.

Tubes are very small.