Two-line accessory handset features DECT 6.0 technology to provide a greater call range without interfering with wireless routers. Smart Call Blocker automatically blocks robocalls from ever ringing through. You can also permanently blacklist up to 1,000 names and numbers with just one touch. Two-line operation allows you to place and receive calls on two different phone lines. Full-duplex speakerphone increases participation by allowing both ends to speak and be heard at the same time for conversations that are more true to life. Caller ID allows you to see the name, number, time and date of incoming calls at a glance. Backlit keypad and display provide excellent visibility in low-light conditions. Accessory handset also includes a phonebook directory, redial, mute, voicemail waiting indicator, volume control and more. Handset is designed for the Vtech Two-Line, Two-Handset Cordless Phone (sold separately).