... IN BOX CallTel T200 Polaris headsets require no amplifier! They plug directly into your headset-ready ... use. Only compatible with telephones with a built-in amplifier. Some specific models: 3Com: 3102 &3103 Telephones ... 600, 705, 710, 720 Ascom: Berkshire 200, 400, 600, 800, SD30, MR30, MR51, MR61 AVAYA / Lucent: 6402D, 6408D ... : 420 and 450Binaural headset photo: Binaural Call center handsfree headset