You've got a T58A or T57W and a Jabra, Plantronics, or Sennheiser headset that just won't talk to each other. The EHS40 is the handshake. USB into the phone, RJ45 or RJ9 out to the headset. Answer, reject, hold, mute, hang up, switch calls – all from the earpiece. Requires firmware version 83 or later on the phone. Plug in, pair, and your operator's free to actually walk around the floor
| 0 | T58A |
| 1 | T57W |
| 2 | T54W |
| 3 | T53W |
| 4 | T53 |
| 5 | T48S |
| 6 | T46S |
| 7 | T42S |
| 8 | T41S |
| 0 | Jabra |
| 1 | Plantronics |
| 2 | Sennheiser |
| 0 | USB 2.0 input |
| 1 | RJ45 (8P8C) output |
| 2 | RJ9 (4P4C) output |
| brand | Yealink |
| firmware_requirement | Version 83 or later |
| category | VoIP Devices & Accessories |
