Panasonic 8 Button 1-Line Backlit LCD Display Digital Telephone w/Full Duplex Speaker Phone Black (KX-DT521-B) This phone is not a standalone phone. It is compatible with Pansaonic digital phone systems such as KX-TDA50, 100, 200, 600, KX-TDE100, 200, 600, KX-NCP500, 1000 and KX-NS700