🔒 Lock it down, but keep control—fast, firm, and removable!
Loctite Threadlocker Blue 242 is a medium-strength adhesive designed to secure 6-19mm metal fasteners against loosening from vibration. It sets quickly in 10 minutes, fully cures in 24 hours, and protects against rust and corrosion while remaining removable with standard hand tools.
D**.
Keeps Bolts Tight Without the Hassle
’ve used Loctite Blue 242 on everything from motorcycle parts to furniture, and it works exactly as advertised. It keeps screws and bolts from vibrating loose, especially on items that see a lot of movement or stress. What I really appreciate is that it’s strong enough to hold, but not so permanent that you can’t remove the fastener later if needed.The application is easy — just a drop on clean threads before tightening, and you're good to go. It sets up nicely and doesn’t make a mess. I’ve had zero issues with rust or corrosion after use, and the bottle has lasted me a long time.Definitely recommend this for anyone who works on machines, tools, or even around the house. Just be sure you’re using it on parts you might want to remove later — this isn't the red (permanent) stuff!
M**.
A Reliable Fix for Loose Screws
This removable threadlocker is designed for nuts, bolts, and fasteners sized 1/4” to 3/4” (6-20mm), perfect for securing scope mounts, rail screws, or even bike and motorcycle parts. Its anaerobic formula cures in 10 minutes and fully sets in 24 hours, locking fasteners against vibration, loosening, and corrosion while sealing out moisture. I applied it to the screws on my Pecawen Picatinny Rail and UTG QD Sling Swivel, and they’ve stayed rock-solid through range sessions and rough handling. The blue formula is removable with hand tools, so you can adjust or remove parts without a torch, unlike red threadlockers. Amazon reviews praise its effectiveness, with one user noting, “It’s perfect for firearms—my scope mount screws haven’t budged” (web:0). The 6 ml tube is small but goes a long way—a tiny drop per bolt is enough, making it cost-effective at $6-$10.
J**E
Long lasting
I purchased this Loctite primarily to secure the optic on my home defense firearm, and it has performed flawlessly. After multiple range sessions and hundreds of rounds fired, my optic hasn't shown even the slightest bit of movement - exactly what I needed for a critical application where reliability is paramount.The product proved so effective that I started using it for household repairs too. Those annoying, constantly-loosening ceiling fan screws that created a shaky noise? Completely silenced after application. The medium-strength formula seems perfect - strong enough to keep things secure, but still allows for disassembly when needed with standard tools.Application was simple with the precise nozzle, and a little goes a long way. I appreciate that it dries clear and doesn't leave messy residue. For anyone needing to secure screws in firearms, machinery, or household items, this Loctite delivers professional-grade results.For those using it for firearm related screws: Always follow manufacturer instructions for firearm applications and allow proper cure time before use.
W**W
Works as expected
Worked well to secure screws on scope rings. Quick arrival and good value on Amazon.
J**E
Great thread locker. recommended product
Must have product for small screws and moving parts that you dont want to lose. Especially useful with firearms for installing sights and other items that need the small screws and what not retained. It is extremely useful and definitely worth the price. It is easy to apply with the dripper style tube. Does not take much especially of the red so this tube should last quite a bit for most people as I bought a tube years ago, use it quite often and still have some left that will last me a long while
S**S
Blue locktite, it is working, keeping a bolt from backing out.
Why did you pick this product vs others?:Good , I used this on a bolt on my motorcycle thatkept coming loose, it is staying in place.
R**I
Always a mess but great none the less
Always dislike how small it is. It’s hard to grasp and there is so little in it. Once you start to use it, it’s very fluid and beings to drip everywhere. Fairly annoying.Either way, the loctite is a great product. Nice that it’s not permanent.
J**.
Did the Job. Locked Down Set Screw.
Kitchen faucet had to be tightened weekly or more with allen wrench. Put a dab of this on the set screw, let set overnight and have not had to tighten since. Going on about 7 months now.
Trustpilot
2 weeks ago
1 month ago