Threadlocker 243 Blue 36ml/1.22oz

Loctite Threadlocker 243 Blue is a medium-strength anaerobic threadlocker designed to prevent fasteners from loosening due to vibration and thermal cycling in mechanical assemblies. This 36ml bottle delivers reliable performance for firearms maintenance, tactical equipment assembly, and general industrial applications where bolt security is critical. The product is ideal for technicians, gunsmiths, and equipment maintenance professionals who require a proven solution for permanent or semi-permanent threaded fastener retention.

The blue formulation of Loctite Threadlocker 243 creates a polymer matrix that cures in the absence of air between mating metal surfaces, eliminating the need for washers or lock nuts on most fasteners. Once cured, it provides medium strength that allows future disassembly with standard hand tools, making it suitable for maintenance-prone components. The liquid consistency ensures complete coverage of thread surfaces, and the compact 36ml bottle allows for precise, controlled application without waste. Typical cure time ranges from 24 hours at room temperature, with full strength development providing superior resistance to vibration-induced loosening.

Field technicians, armorer-level firearm owners, and maintenance crews benefit most from this versatile threadlocker for barrel nut installation, scope mount assembly, and rail system fastening. It performs exceptionally on fasteners ranging from 1/4" to 3/4" diameter and is compatible with steel, iron, and most alloy fastening applications. The medium-strength formula ensures that critical components can be tightened securely without risk of permanent seizing, making it the standard choice for equipment that requires periodic maintenance or component replacement.