Before traffic signal electricians in Los Angeles began using wire connectors from King Safety Products, St. Charles, Mo., they used the "dip-and-tape" method to seal splices and make repairs. They'd coat each splice with a dip-on insulator, then wrap the splice with layer-upon-layer of electrical tape. Each splice took 5 to 10 min.

In contrast, King waterproof connectors twist on or off in just 30 sec. Electricians simply insert wires through retention fingers at the base of the connector body, then twist. Inside, a square-wire spring grips wires and holds them in place. Furthermore, the connectors are prefilled with a nonhardening, nonconductive dielectric silicone sealant. Even with misapplication, just one millimeter of sealant provides up to 500 V of protection against internal arcing and flashover.

Tough, color-coded connector bodies are impact-resistant plastic with thick walls. Waterproof connectors are UL-50 tested and meet the requirements of NEC 110-11. Underground and Dry and Damp connectors are also available.