... require no amplifier! They plug directly into your headset-ready telephone! What's in the box: Headset shown above, plus a ... Ascom: Berkshire 200, 400, 600, 800, SD30, MR30, MR51, MR61 AVAYA / Lucent: 6402D, 6408D+, 6416D+M, 6424D+M, 8403, 8410D, 8434DX ... Phone and 48-Key Digital Feature Phones General Electric: GE Telephone Model 2-9451, 2-9490 GrandStream IP Phones: Budgetone 101 ...