KX-TG3021S Panasonic 2.4 GHz Expandable Digital Cordless Phone Digital 2.4GHz Frequency Hopping Spread Spectrum Cordless Phone Expandable up to 4 Total Cordless Handsets with Intercom Capability Digital Handsfree Speakerphone on Handset 50-Station Phonebook and Dialer Call Waiting Caller ID