The 113-gram (four ounce) "Wristomo" silver-bodied watch-phone pops off the wrist at the push of two buttons, allowing it to be used like a normal cellphone.

It can withstand sweat, rain or splashes of water from washing, said NTT DoCoMo Inc., Japan's leading mobile phone company.

The new phone will begin selling for 37,000 yen (310 dollars) on May 7 through Internet orders only.

"Because of its special qualities, we are not going to use our regular distribution channels," said DoCoMo spokesman Nobuyuki Hatanaka. "We are selling it on an experimental basis on the Internet."

The company used its older PHS technology for the phone, which allowed for a smaller body size and decreased battery drain.

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