- Accessory Handset- Accessory handset only - requires base unit to operate- Compatible AT&T Phones: EL52265, EL52345, EL52365, EL52106, EL52206, EL52256, EL52306, EL52346, EL52356, EL52406- Up to 5 handsets can be registered to a single base- Caller ID, call waiting- 30 name and number caller ID history- Simulated full duplex handset speakerphone- Extra large display for easy viewing