Fujitsu Computer Systems on Monday started offering in the United States for the first time sold-state drives as an option in ultra-portable computers, making the machines more durable for work in the field.

The Samsung drives are available as an alternative to traditional hard drives in the LifeBook P1610 and B6210, both touch-screen notebooks. The flash-memory drives come in 16 Gbytes or 32 Gbytes, and carry a premium of $500 and $1,300, respectively.

The additional cost is justified through a longer-lasting computer, says Paul Moore, senior director of mobile product marketing. With no moving parts, solid-state drives are not easily damaged, and can survive impacts far greater than a hard drive. In addition, these drives use less power, generate less heat, and boot faster.

Customers of Fujitsu LifeBooks are in industries where workers need a light and compact, but highly durable, mobile computer. The vertical markets include health care, aviation, and field service, such as delivery people. Ultra-portables are also used on the trading floor on Wall Street.

The P1610 weighs 2.2 pounds, and has an 8.9-inch indoor/outdoor screen. The B6210 weights 3.2 pounds, and has a 12-inch screen. Both are available in rubberized cases for better protection against banging. The feature costs an additional $139.

Fujitsu is targeting companies looking to buy around 50 computers or more, Moore says. Pricing will depend on configuration and volume. High-end, ultra-portable computers sold in Japan with solid-state drives can cost as much as $4,000 apiece.

While still far more expensive than hard-disk drives, solid-state drives have been coming down in price, which has boosted demand. Last week, SanDisk introduced its first 32-Gbyte drive, and Intel launched an 8-Gbyte drive.