Corrosion-resistant electroless nickel-coated brass blades, contacts, terminal screws and wiring clamps and stainless steel assembly screws make these devices ideal for use in wet and corrosive environments. EPTR rubber part provides outstanding resistance to wet and damp environments, extreme temperature variations, water, acids, alkalis, grease, oils and many automotive and industrial lubricants and solvents. Plug and connector husk is molded to a bondable nylon body, providing a device that withstands physical abuse. Interlocking tongue and groove construction seals out water, moisture and dirt when plugs are mated with connectors. Multi-point sealing system utilizes nut, strain relief washer and rubber bushing to form a watertight cord grip seal. Non-magnetic stainless steel fast-threading assembly screws won't interfere with sensitive equipment.