US Patent 7473024 Light strings including standard socket and longer-length non-standard keyed socket

A light for use in light strings has a deeper socket, a longer base and longer Dumet wires than a standard socket, base, and Dumet wires so that the standard bases and bulbs will not operate in the non-standard socket. Furthermore, the base and sockets are keyed so that they are restricted to at most two orientations with respect to each other and cannot be twisted with respect to each other.