Enjoy the clarity and reliability of a landline phone, with easy-to-use features that make your work and home life easier. Panasonic Cordless Phone KX-TGD664M is a 4-handset home phone system expandable up to 6 handsets, with an integrated Digital Answering machine to make sure you never miss a message. Make even your cell calls more clear by using Link2Cell to connect your mobile phone to your landline, giving landline-level call clarity to every cell call that comes through. And no need to worry about draining the battery -- an audible Low Battery Alert lets you know when the battery needs charging, and more. Noise Reduction Technology helps make every call as clear as possible by reducing the surrounding noise coming from the other party's telephone. A robust Call Block system allows 1-step blocking up to 150 nuisance callers with the touch of a button, while a Phone book of up to 3,000 numbers makes sure all your important contacts easily accessible. A range of hands-free phone functions lets you enjoy mobility and flexibility--full duplex speakerphone lets you use your handset hands-free; handset can be used as a baby monitor even while away from home. Bilingual Caller ID lets you customize your caller ID to display in English or Spanish and get caller announcements in that same language so you can hear who is calling, even when you're across the room (note: caller ID requires additional service through your local phone company). *This model does not have a jack for connecting headsets.