Trisonic TS-650 Black 50' Ft Modular Coil Cord, specially designed to be used with a phone, fax machine, or any other device that requires a telephone cord. This cord features modular plugs at both ends and it's compatible with 2 or 4 wire systems. This cord is easy and simple to use, just remove old coil cord from telephone and handset, then plug one end of modular coil cord into handset, and plug the other end of the modular coil cord into the base of the telephone.