ADDITIONAL CORDLESS HANDSET: Compatible only with compatible with Panasonic KX-TGD51x/KX-TGD53x/KX-TGD56x series, easy setup/pairing with phone base ONE-TOUCH TELEPHONE CALL : Register up to 150 numbers with one-touch Call on the cordless phone base unit & cordless handsets. Compatible with Aid T-Coil (TIA-1083 Compliant) BILINGUAL CALLER ID: Set your talking Caller ID to audibly announce caller information in either English or Spanish from the telephone’s base unit and cordless handsets when you can't view the screen SEE YOUR MESSAGES EASILY AND INSTANTLY: Quick-read message counter lets you instantly know how many phone messages you have received with a large, easy-to-read message counter on the phone system's elegant cordless base unit SECURE, LONG-RANGE PHONE SIGNAL: DECT 6.0 technology offers a long-range cordless phone and is ideal for homes and apartments with thick walls