Pass Seymour® Turnlok® Connector. NEMA L9-30R configuration number. 4-wire non-grounding. Quick-thread assembly screws and cord-grip screws come backed-out, ready-to-wire. Industrial-strength, brass alloy plug blades and connector contacts resist heat rise, provide excellent conductivity. Raised ribs provide non-slip gripping profile for turning to lock and unlock. Double dovetail design provides superior protection against cord pull-out forces. Impact and corrosion-resistant durable nylon 6 shell material. Rounded back contour reduces snags and hang-ups on the job site. Scallop shell design provides non-slip gripping surface for insertion and withdrawal. Visible stamped NEMA configuration and device rating. New-design external cord grips provide visible assurance of safe and proper cord retention. Integral flexible rubber cord grommet conforms to and seals around SO cord to provide protection from oils, water or chips entering wiring chamber.