Citizen Band radio (also known as walkie talkie), a handheld transceiver is a hand-held, portable, two-way radio transceiver.
Major characteristics of CB radio are:

• Only one user can transmit at a time, though any number can listen and a "push-to-talk" switch that starts transmission.
• Typical CB radio resembles a telephone handset, possibly slightly larger but still a single unit, with an antenna sticking out of the top.
• The built-in speaker in CB radio can be heard by the user and those in the user's immediate vicinity.
• Hand-held transceivers may be used to communicate between each other, or to vehicle-mounted or base stations.
• It is widely used in any setting where portable radio communications are necessary, including public safety, military, outdoor recreation.
• Devices are available at a price range of $40-$400.

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• http://en.wikipedia.org/wiki/Walkie-talkie
• http://www.lightinthebox.com/producttags/W-Walkie-Talkie/