"Several years ago I was advised by a plumbing Company to try LS-X, when I explained about leaking undersink connections on my American RV, (difficult to get replacement parts). I tried it, and it worked! Like most other reviewers, I suggest that you keep the tube wrapped in cling-film, as the paste does go off rather quickly. But I have managed to use the paste from the same tube over several years, I just keep cutting the tube as necessary. And yes, even old paste works well. New house, leaking CH pump connections. I fitted new fibre washers, the originals being destroyed. A squeeze of LS-X either side of the washers, tighten the pump up, wait two hours, open valves and turn on the central heating. No leaks, and we are now 72 hours later. LS-X is worth every penny."
"Had a couple of weeping connections on new radiators on which I had used traditional PTFE tape without success. Bought this LS-X sealer as a last resort, dismantled and refitted the joints using the LS-X and no leaks since. This is a first rate product and in my opinion essential for all compression/threaded plumbing connections."
"After three go's at fixing a weeping immersion heater that had been seeping for many years looking at the limescale around it, and thoroughly cleaning it each time, using a new gasket and only a little PTFE tape on the thread to lubricate, I finally decided to try LS-X. Drained it down again, a thin smear around both sides of the gasket (using the thin brown hard fibre type this time as opposed to the thicker softer ones} and after a week not a drop. Perfect seal, no dampness at all around the boss which is something I couldn't achieve before. So I am sold on LS-X . I am an old SEEBOARD electrician and in the 60's we used to fit loads of immersions using the brown fibre gasket and Boss White in those days, but as is said elsewhere difficult to get out again."
"I use on all threaded plumbing joints with great success. As noted before, it does go off quickly so I put lid on quick and wrap in clingfilm. It makes idiots like me look like half decent plumbers. Very pleased with it so far."
"I have used several tubes now on different plumbing jobs seals quickly even in wet. A must have for the plumb bag/toolkit as you never know when you need it. Only thing to point out the sealant goes off very fast so make sure you put the top back on the tube asap!!"
"Been using this for years, works where nothing else will. So good I'm not even tempted to try other products any more, just make sure you put the lid back on straight away as it goes off in the tube if left unsealed."
"First time using this. Needed to get a seal on some older style radiators and was struggling with just PTFE tape. Smeared some of this sealer and left overnight. No problem with any of the rads. Perfect."
"Brilliant stuff. I use it on all non soldered copper joints and many plastic ones. It is excellent for sealing some difficult joints like flexible pipes on pond construction. Be careful to keep the cap and screw thread clean or the stuff will dry up quite quickly. A little expensive for what it is but is does the job extremely well and remains flexible. If you should need to break the joint open in the future the stuff peels off easily ready for another application before tightening the joint again."
"I've now been using LS-X across any number of plumbing applications for years and this compound - because contact with water helps it cure - has never let me down. If I want to be doubly sure that a foam ring or neoprene washer is properly seated and secure, I always add a ring of LS-X. You can't go wrong and you save yourself an awful lot of time and repacking seals."