Uniden America unveiled a 5.8GHz digital expandable corded/cordless phone with built-in VoIP capability. 
Featuring 5.8GHz technology, the product is compatible with Uniden’s TCX800, TCX400, TCX440 color screen phone. Key features includes call waiting, caller ID, handset speakerphone, four-way conferencing, DirectLink two-way radio capability and a do not disturb setting.
http://www.uniden.com