The Yealink Headset Adapter EHS40 connects to the UPS of your phone
Compatible with Jabra, Plantronics and Sennheiser headsets
Compatible with Yealink SIP-T58A, SIP-T57W, SIP-T54W, SIP-T53W, SIP-T53, SIP-T48S, SIP-T46S, SIP-T42S and SIP-T41S, as well as T48U, T46U, T43U and T42U IP phones