Allen Tel AT173 4 Conductor, 6 Position Plug, Accomodates Two Single-Line and One Two Line Telephones Triplex Modular Adapter Triplex modular adapter Designed for use with a line jack arranged for a 2-line telephone system in accordance with USOC RJ14C and RJ14W Consists of a 4-conductor, 6-position modular plug internally wired to three modular jacks as per the wiring diagram Two single telephone sets and a 2-line set are accommodated Comes with Allen Tel Products' standard 1 year warranty