Japanese carrier KDDI has unveiled a 3G mobile phone that lets users hear a conversation through their bones, a technique it claims can give a much clearer conversation in noisy environments.

KDDI's A1407PT: a new take on most 'dog and bone' designs

The A1407PT clamshell, which is manufactured by South Korean firm Pantech, has a loudspeaker inside its lid that can send out sound at a frequency that allows talk to be transmitted as vibrations through the bones in the user's skull straight through to the inner ear.

While this bone conduction technique isn’t new - for example, manufacturer Thanko has already developed a pair of headphones based on it - the technology’s rarely seen inside a dog and bone... sorry... phone.

However, the technology is battery hungry: the phone gives five hours of usage time when the function’s turned off and just three-and-a-half hours when turned on.

Unfortunately, the rest of the 5.1 x 9.8 x 2.0cm CDMA 1X handset is fairly ordinary: it includes a 2.4in internal display, 1.3-megapixel camera and - how retro - an infrared communication port.

The phone is available to buy now on the KDDI network in Japan for about ¥20,000 (£84/€121/$171).