FeaturesDesign locks resilient sealing material in stainless steelSteel retainer protects seal from extruding out under torque and limits compression to an optimum predetermined value, provides high quality sealResilient material flows and seals rough edgesWhen used with an externally threaded connector provides a tight seal against oil, fumes or moisture at the knockout openingNEMA 3R/4/6/13 enclosureRubber seal