Loctite® 243™ Primeless threadlocker is designed for the locking and sealing of threaded fasteners between 1/4" and 3/4" (6 to 20 mm), which require normal disassembly with standard hand tools. Product cures when confined in the absence of air between close fitting metal surfaces and prevents loosening and leakage from shock and vibration. The thixotropic nature of Loctite 243 reduces the migration of liquid product after application to the substrate. Provides robust curing performance. It not only works on active metals (e.g. brass, copper) but also on passive substrates such as stainless steel and plated surfaces. Offers high temperature performance and oil tolerance. Tolerates minor surface contaminations from various oils, such as cutting, lubrication, anti-corrosion and protection fluids.