Loctite 518 is a medium-strength, general purpose gasketing product with excellent contamination tolerance. Ideal for use on casted iron, steel and aluminum flanges. LOCTITE® 518 cures when confined in the absence of air between close-fitting metal surfaces. It is an anaerobic gasketing material designed for use on rigid iron, aluminum, and steel flanged mating surfaces. Fills gaps up to 0.25mm and forms a flexible, chemical-resistant seal that will not tear or decay. Parts disassemble easily, even after extended service. Typical applications include sealing close-fitting joints between rigid metal faces and flanges. It is also used as a formed-in-place gasket on rigid flanged connections, e.g. transmissions and motor housings. NEW: Henkel has recently improved the product formulation of LOCTITE 518 providing higher strength on contaminated surfaces, better flexibility and improved adhesion, enhanced sealing capability, improved gap cure, and high performance on passive metals without an activator.