DESC: The Avaya 8400 SOTA Series One Touch Adapter allows Plantronics headset users to initiate, answer and end calls without lifting their telephone handset receiver off the cradle. This item is only intended for those with AT&T, Lucent or Avaya 7400-series and 8400-series telephones only (includes 7406, 7410, 8410D, 8411D, 8434 and others in these series with adjunct ports). This unit plugs into the adjunct port of your Avaya phone; includes all necessary connector cables and cords, AC power adapter, convenient QuickDisconnect, mute and incoming volume control. Use with anyPlantronics H-series headsetor Avaya Freedom of Choice headset. (Note: Replaces former part number Avaya 500AM and is also referred to by Avaya Comcode 700 304 058.) One-year factory warranty.