

🔧 Seal it fast, seal it right — don’t let leaks slow your flow!
Loctite 577 is a medium-strength, polymer-based thread sealant designed for metal pipes and fittings. It provides instant low-pressure sealing and locking, cures without a primer on lightly contaminated surfaces, and offers excellent chemical and thermal resistance. Its gel-like formula minimizes migration, making it ideal for fast, clean applications even at low temperatures.

| ASIN | B01LPJ3LIM |
| Best Sellers Rank | #39,476 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #48 in Industrial Thread Sealants |
| Brand | Loctite |
| Brand Name | Loctite |
| Color | Yellow |
| Compatible Material | Metal |
| Customer Reviews | 4.6 out of 5 stars 126 Reviews |
| Included Components | Loctite 577 - General purpose thread sealant for metal pipes and fittings: 50 ml |
| Item Dimensions | 1 x 1 x 1 inches |
| Item Form | Gel, Liquid |
| Item Weight | 1.04 ounces |
| Item dimensions L x W x H | 1 x 1 x 1 inches |
| Manufacturer | Loctite |
| Material | Polymer-based material |
| Material Type | Polymer-based material |
| Style | Compact |
| Style Name | Compact |
| Supported Standards | NSF |
| Surface Recommendation | Metal |
| UPC | 079340010475 |
| Unit Count | 1.0 Count |
| Water Resistance Level | Water Resistant |
A**.
Loctite 577
Works as it should. New in tube, known quality, super fast shipping!
V**.
Thread sealer
Great product works as describe
M**K
Works great on PVC, SS, and Brass
You have to shake it a lot to mix it if it's been sitting at all. I keep it in the refrigerator hoping that will preserve its shelf life which isn't listed as that long for a non-professional. I usually use teflon tape or the liquid teflon even more. However, you still need to max torque on the fittings and some of the Chinese SS & Brass fittings still leak. If you've got elbows or tees that need a particular alignment, best fitting torque often puts me 180-270 deg. out of alignment. This stuff works great to seal (I was using less than 80 psi) water fittings with a mild snug fit and yet without excess force, is removable. Leaves a lot to clean up on the threads but an easy job. Now my go-to sealant for pipe threads I would typically glue or solder or epoxy. Hope it stores well in the refrig.
C**C
works but spendy
product worked as expected though quite spendy
G**.
Great product by a trusted manufacture
Excellent choice for sealing gas fitting, easy to apply, a little pricey but well worth it for piece of mind that you will have no leaks
K**R
It works
Works as intended
P**W
Does the trick
Used this on a recent solar panel install on a van and so far have been quite happy. Seems to have sealed all of the rivets and bolts used in the install. Even in the blazing sun, have plenty of time to work with this stuff. Application is easy once you get the bottle open; you have to pull the nozzle away from the body to open it. There is some significant extra run off once you close it again, so take that into consideration when applying.
P**N
Great Loctite brand!
Great pipe thread sealant!
Trustpilot
3 weeks ago
2 days ago