Product Features Amplifies incoming sound up to 50 dBHDS (Hi-Definition Sound) technology makes every word crisp and clearDigital Tone Control enhances voice tone and pitch making difficult to hear words easy to understandTalking Caller ID with Call-waiting announces the caller's number in English or FrenchEasy to use 150 name and number phonebookCall history lists incoming, missed and outgoing calls for your convenienceThree selectable languages (English, French, and Spanish) on handset displayBack-lit talk-back keys confirm if you've pressed the desired numberOne-touch call-for-help button for hands-free emergency callsThree (3) one-touch speed-dial buttons;High performance speakerphone on handsetBright visual ring flasher and super loud ringer (95 dB) on handset and baseDECT 6.0 technology for superior range and interference-free callsBase battery back-up (4 AAA batteries, not included) for full operation during a power outage. Batteries can be used on the handset if neededOutput jack for tele-coil, neck-loop and other assistive accessories for hearing aid and cochlear implant usersHearing aid compatible handsetExpandable up to four (4) handsets (sold separately)