Refrigeration Technologies RT201B Nylog Gasket/Thread Sealant, 30 ml (1 Pack)

The Refrigeration Technologies RT201B Nylog Gasket/Thread Sealant is an excellent product for HVAC and refrigeration work. I've used it on flare fittings, threaded connections, O-rings, and gaskets, and it consistently helps create leak-free seals. Unlike traditional thread sealants, Nylog remains flexible and does not harden, making future maintenance and disassembly much easier. What stands out most is its compatibility with refrigerants and compressor oils. It lubricates connections during assembly while providing an extra layer of protection against leaks. A small amount goes a long way, so the 30 ml bottle lasts much longer than expected. The sealant is easy to apply, stays in place, and performs well even in systems exposed to vibration and temperature changes. It's a trusted product among HVAC professionals for good reason. Overall, if you're working on refrigeration or air conditioning systems and want a dependable sealant that won't contaminate the system, the RT201B Nylog Blue is a worthwhile addition to your toolbox. Highly recommended.

The Nylog arrived promptly. Used it in the installation of a mini-split. The product is easy to use. The mini-split has been working beautifully with no refrigerant leaks during testing and operation for about three days so far.

used to install Minisplit, works well, good reassurance for long lasting seals. Used as recommended on head of cones where the flare joins, putting several mini-splits on an older home retrofit. Easy to use, ample supply for multiple applications. Seems wise to prevent possible leakage for the price compared to replacing lost refrigerant on a DIYer.

Seals compression fittings on pipes. Expensive, and worth it. Replacing lost refrigerant cost much more.

Good quality stuff, well worth having it, i don't know how effective it is, because i never had a leak that i put it on that then fixed it or something like that, but i haven't had a leak on connections i have used it on, so thats something! Overall easy to use, and definitely worth going the belt and suspenders route when most refrigerants are so expensive now.

This stuff is sticky so wear gloves when applying. Works very well to take up small gaps around o-ring seats to seal high pressure A/C systems. If you're using UV leak detector, this goop glows bright blue, where the UV detector glow bright yellow/green. There is no accidentally mistaking one for the other.

Peace of mind and works well on hydraulic flares too.

The best refrigerant sealer I have ever used