... modular plug into the headset jack on your phone (phone must be headset-ready, see list below ... 200, 400, 600, 800, SD30, MR30, MR51, MR61 AVAYA / Lucent: 6402D, 6408D+, 6416D+M, 6424D+M, 8403 ... 8434DX 4406D+, 4412D+, 4424D+, 4424LD+ 2410, 2420 4610, 4620, 4621 5410, 5420 5610, 5620 DT1, DT3, DT5 ... IP601 IP Phones Safecom: SDSIP-500IP SIP Phones ShoreTel Phone: IP100, IP212K, IP230, IP265, IP530, IP560, ...