Loctite 242 Threadlocker
The everyday medium-strength blue threadlocker. Sized for 1/4" to 3/4" fasteners, it locks against vibration and seals against corrosion. Removes with standard hand tools when service is needed.
From delicate electronics to heavy industrial equipment, Loctite locks threads and helps reduce unplanned downtime.
The original anaerobic threadlocker, engineered for industrial reliability across every fastener size and grade.
Threaded fasteners loosen because of side-sliding and shifting between the threads, not because they untwist. Loctite anaerobic threadlockers fill the clearance, cure to a solid, and stop the side-shift that causes vibration loosening.
The result: longer service intervals, fewer repeat repairs, and one product family that covers everything from delicate electronics to heavy industrial equipment.
Applied® stocks the full Loctite lineup at regional centers across North America.


Loctite color codes tell you the strength at a glance. Purple for low, blue for medium, red for high, plus instant adhesives for fast bonding.
The everyday medium-strength blue threadlocker. Sized for 1/4" to 3/4" fasteners, it locks against vibration and seals against corrosion. Removes with standard hand tools when service is needed.

High strength red threadlocker for permanent assemblies. Use on critical bolts that must not loosen.

Low strength purple threadlocker for fasteners under 1/4". Easy disassembly for adjustment screws and small fasteners.

Fast-setting Loctite instant adhesives bond a wide range of materials. New and improved HQ- and MMBP-free formulations support safer handling.
Apply to clean threads, let it cure, then disassemble when needed. The chart below walks through the full process.

Quick answers to the questions maintenance teams ask most.
Loctite Corporation, now part of Henkel, invented the anaerobic threadlocker fifty years ago. The technology changed threaded assembly reliability and remains an industry standard. Applied® carries the full Loctite lineup at regional centers across North America.
See how Loctite threadlockers solve real threaded fastener problems on the shop floor.
The fundamentals of anaerobic threadlocking and why it outperforms mechanical locking devices.
Proper application technique for reliable bonding on industrial threaded assemblies.
Walk through the four factors that determine which Loctite threadlocker fits your job.
Compare anaerobic threadlocking performance against traditional fastener locking methods.
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The above content is provided “AS IS”, AND ANY AND ALL EXPRESS AND IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS ARE HEREBY EXCLUDED.
All warranties, if any, are solely from the supplier.
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