Up to 40 dB adjustable amplification Adjustable tone control clarifies sound, making words easy to understand Full duplex speakerphone in handset with adjustable amplification DECT 6.0 technology 6-level ringer volume control & 10 ring tones Bright visual ringer & vibrating handset Talking caller ID, keypad, & phonebook Big button easy-to-read high contrast keypad 30 name/number caller ID Expandable up to 4 additional handsets 4 one-touch memory dial buttons 200 name & number phonebook directory One year warranty