This cable features a Plantronics Quick Disconnect (QD) plug compatible with H-Series headsets including the EncorePro, DuoPro and TriStar. Simply plug it into your headset and connect the modular telephone plug at the other end to your compatible Plantronics amplifier or phone. The springy coiled cord ensures a tidy cable that can stretch if necessary. This item has been specifically designed for a lengthy 4 hour use, comes complete with a wonderfully crafted, coiled cord that is compact but extendable. As such, there is nothing better for flexible, hands free communication.