Panasonic kx-tg3611 cordless phone 2.4 ghz frequency hopping spread spectrum (fhss) technology fhss technology provides clear sound over longer ranges, as well as digital security to prevent eavesdropping. digital speakerphone (handset) you can answer the phone without interrupting what you're doing - whether you're cooking, cleaning, or surfing the internet. light-up indicator with ringer alert (handset) the indicator on the handset lights up in amber when there is an incoming call for visual confirmation. convenient aaa (r03) ni-mh rechargeable battery (handset) since aaa-type rechargeable batteries are used, you can replace them with two commercially available aaa batteries for added convenience. (rechargeable battery: hhr-4mrt) illuminated display (handset)