Spray them with water, subject them to extreme temperatures or drop them on the ground, NEC's rugged ShieldPro laptops are made to survive rough treatment. The biggest challenge, however, is about to come: battling more established competitors in the harsh international market.

It was in January of last year that NEC entered Japan's market for rugged PCs, a segment that was at the time monopolized by Panasonic. Since then it has grabbed a 10 percent share of that market, and the company is now heading overseas to conquer other markets.

Despite a larger number of competitors in the international arena, NEC is determined it establish itself internationally and will initially target government agencies and construction companies in Europe, North America and Australia, said Takanori Kawanaka, who will help sell the laptops overseas.

NEC hopes to sell 50,000 of the ShieldPro models in the next two years, 30,000 of them outside Japan. In the same period it also hopes to boost its domestic market share from 10 percent to 40 percent.

To spearhead its expansion, NEC added a new model, the N22A, to the ShieldPro range on Thursday.

The N22A has a number of advances on the previous model, such as an Intel Core 2 Duo processor, 80GB of memory, a brighter 750cd/m (candela per square meter) screen and an optional high-capacity battery that lasts up to 12 hours.

Its IP rating, an environmental protection rating developed by the European Committee for Electrotechnical Standardization (CENELEC), also increased to IP55, which means that can tolerate a direct spray of water while the previous model could withstand just splashes.

New is a series of enclosures designed to fit around the PC's ports so that cables can stay plugged in or PC Card modems be operated without allowing water into the machine.

Like the previous model, the N22A can function between 5 degrees and 45 degrees Celsius or, if specified at the time of ordering, be constructed to operate at between -20 degrees and 50 degrees Celsius for additional cost.

It can survive a drop from up to 90 centimeters, which is approximately the height when carried close to the waist, as NEC demonstrated at a Tokyo news conference. A member of the NEC Greens rugby team dropped the PC, it hit a hard wooden board with a bang but Windows XP started right-up as normal.

The N22A is available build-to-order from NEC in Japan at prices starting from ¥300,000 ($2,900). It will hit international markets by the end of this year.