Waterless Trap Seal, 4 Inch

Its good quality

edit (2025): after about one year of use it stopped working completely because rubber lost its elasticity. I started smelling sewer gas, after investigation took it out. Rubber hangs down leaving visible gaps between rubber, making it completely ineffective. The problem is with the largest one (4 inches). old comment: It works - somewhat. Each reduces sewer gas by a significant percentage, but not completely. I had to put in 3 at once to make it reasonably effective. Of course it depends how big your initial sewer gas issue was. One problem is that the silicone is soft and can be blown up by gas pressure. Its main advantage compared to other types that can be put inside a pipe is its resistance to dirt. I also tested spring and magnet traps, and they work perfect when they are clean, but they seem much more prone to things getting stuck in them (like hair) stopping them from working. Small water traps are perfect when filled with water, but they dry out easily and also have a tendency to fill with dirt. They should make a version with 3 seals in one.

Not strong enough and water goam can break out easily.

Incorrect information, the size specifically says 3.5 inches and not 4 as claimed

It is made of very soft plastic that insects, backflow or gas can push through

No it didnt meet my expectation

عمليه جدا لكن ربما تحتاج تعديل وتصغير بسيط لتدخل في البلاعه

Just moved into a new house. We have a drainage hole in the floor of our furnace room. No P-trap, just goes straight into the sewage line. Stunk to high heaven. Smelled sometimes of farts, sometimes of animal, sometimes of both. Thought the smell would go away, but after a month it was only getting worse. Evenings our basement and main floor would smell like the inside of a public washroom. Did some googling and found out you can install one-way valves on pipes like this. Ordered the waterless trap seal, it came three days later, and bingo-bango no more sewage gas venting into our basement (which is also where we sleep, so SUPER happy to have this problem fixed). Rarely do I encounter problems in our new house that are this simple to fix. Seal's been in for a week now, and so far no issues. Drains as much water as I can throw at it. Poured several gallons of water onto it just to be sure, and it drained the water faster than I could pour it. So I have no worries about it being able to keep up with the drainage pipes I've got pointed at it right now (furnace, boiler, and dehumidifier).

Fits well into a 10cm pipe and very easily installed. Appears to do what it's there for. Very dependent on some thin rubber I'm a little worried about the longevity of. Will see in 5 years time.

Ideal just what we wanted stop the smell returning works well thank you was delivered nice and quick as well

Purchased to prevent smell coming up from the washroom 4" drain hole. Is easy to install and so far it the smell have gone away. Also it will prevent any bugs coming up through the drain. Very happy!