"I fitted a new rad in my daughters bedroom but couldn't stop one of the outlets from weeping. I had initially used PTFE tape on the thread, and ended up taking the rad off the wall, draining it and re-taping the leaking outlet (have used PTFE a few times before with no problems). It still leaked though so not sure if it was just a problem with the thread of the fitting itself or inside the radiator. Anyhow, saw this stuff and thought I'd give it a go, worked a treat, smeared a small amount around the outlet and haven't had any water coming out since."
"I have only ever used this product so I don't know how it compares with other products. But if it works as LS-X does there is no need to change. This seals a joint when PTFE tape won't work effectively enough. I wipe the sealant around the thread and then tighten the joint if that is an option but sometimes you need to spread it on externally. I really don't understand how this works against the pressure of the water but it seems to. Keep one of these in your plumbing kit you never know when you might need it or when a friend might ask you to borrow it. There are various tips for keeping it fresh once opened but if the end of it clogs impossibly and there is still some squidgy in the middle just puncture the tube to get to the sealant and wrap the tube up in cling film."
"Great product that has got me out of many a sticky issue. Used to seal syphon to toilet cistern - worked a treat. also used this to provide a thin invisible seal around the rear lights on a classic car. Totally invisible yet stopped a leak into the boot that I've had for years. At this price, you can't afford not to have this in your tool box."
"Spent 2 days trying to fit new waste to an old sink, using all sorts of mastic/adhesive etc with no joy, then a friend told me about fernox lax, spent an hour removing all the stuff I put on, and put a smearing of this stuff and wow, no more leaks. Its early days but this seems to do the job very well."
"I was installing new tap inserts, I turned of the hot and cold water both controlled with ball o fix valves, one of the valves started leaking around the slotted head used to turn the valve on and off.
The valve is difficult to get at to replace it and I would have to drain down the system to do it, I needed a quick fix and this product did the job. It now means that I can replace the valve during the summer and at a time to suit me.
Excellent product would thoroughly recommend it, easy to apply and it works quickly even when used externally, just make sure you wear gloves to apply it.
"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."