By Western Electric Co. Inc. of Chicago, Illinois. Extension cord used with the T-30 throatmicrophone. The microphone plug was inserted into the 2-pin socket of the extension cord (JK-48). The cord has an inline 'push to talk' switch, SW141-AC, and a black PL-68 jackplug for connecting with the aircraft intercom. A cord enabled the airman to hang the extension cable around the neck. Excellent, probably unissued condition with tatty box of issue. Stock code H18426.