KX-DDT521X

Display: 1-line (16-character) LCD with backlight
Quick Buttons: 8 programmable buttons (with LED indicator for busy/occupied line status)
Audio: Full duplex speaker (allows for immediate two-way communication without audio interruption)
Connectivity: Headset jack (2.5 mm) and Digital Extra Device Port (DXDP)
Limitations: Compatible only with Panasonic PBX systems (NS, TDA, TDE, NCP series). Not compatible with NEC systems.
1 year warranty