The Panasonic KX-TGE474S expandable Digital Enhanced Cordless Telecommunications (DECT) 6. 0* Phone system with answering machine and 4 cordless handsets allows you to link up to two cell or smart phones and integrate them into the phone system via Bluetooth. Includes one cordless handset in the base unit and four additional cordless handsets, expandable up to six handsets (additional handsets sold separately). hear who's calling from across the room without having to get up using text-to-speech announcements in English and/or Spanish from the phones? base unit and portable wireless cordless handsets. Attach the optional key detector to your car key ring or other easily misplaced items and forget about ever losing them ever again. Using any of your telephone handsets, you can activate the key Detector's beeping alarm and quickly track down your lost keys. Key Detector's powerful range finds objects up to 200 yards away so you'll find whatever's lost whether it's upstairs, in your car or in the yard. You can register up to four key detectors and give each a distinctive name, like Dave's keys or Sharon's keys. Easy call block, speakerphone, voice paging, and advanced TAD (telephone answering device) functions tie it all together making this system one of the most reliable and functional systems available in the market today. Guided feature tutorials are available for this cordless phone on the manufacturer?s website. Disclaimer: * DECT 6. 0 is a North American marketing term for DECT devices manufactured for the United States and Canada operating at 1. 9 GHz.