Permatex Anaerobic Flange Sealant is a flexible gasketing material for use on rigid machined flanges with less than .015″ gap. This OEM approved Anaerobic Flange Sealant can be used where OE’s specify “anaerobic gasket (cures in the absence of air). Permatex Anaerobic Flange Sealant eliminates the need for preformed, paper, rubber and cork gaskets and flexes with flanges that move in service.