This Direct Connect GN 2125 NCD Headset works with telephones that have built-in amplifiers. Direct Connect headsets feature a Quick Disconnect coil cord, with the ultra-reliable GN Netcom Quick Disconnect on one end and a modular plug on the other. It is also a binaural headset with sound in both ears, providing users an advantage in noisy environments. It features a single-cable binaural design, transmitting sound to both ears without using a yoke configuration. Having only a single-cable extending down one side of the headset enhances user comfort and ease of use.