HP has launched new ultraportable laptops in the US that can easily switch between wireless 3G broadband networks and withstand harsh environmental conditions.

HP's EliteBook 2530p ultraportable and EliteBook 2730p tablet PC have been tested to meet the US military's standards to withstand harsh elements like high altitude and temperatures, the company said.

The laptops, targeted at business users, have also been designed for sensitive parts like hard drive or displays to withstand impact on falls, said Keith LeFebvre, vice president and general manager at HP.

Gobi wireless technology from Qualcomm allows the laptops to seamlessly switch between 3G networks, LeFebvre said. With the technology, users can decide to change 3G networks without changing the hardware.

All users have to do is change firmware, which changes the 3G radio. The chip supports EV-DO (Evolution-Data Optimized) and HSUPA (High-Speed Uplink Packet Access) 3G technologies. In the US, users will be able to switch between 3G services from Verizon, Sprint and AT&T, LeFebvre said. Depending on the wireless technology, users will be able to switch between other 3G networks worldwide.

The new laptops also have a unique feature to read business cards and convert them to text. Users can place a business card into a slot carved into the front of a laptop, after which the webcam shoots its picture. Software extracts important contents from the business card - including names, addresses and phone numbers - and converts it to text. The data is then transferred to a file.

The EliteBook 2530p comes with a 12.1in screen and weighs 3.19 pounds, with prices starting at $1,499 (£750).

The EliteBook 2730p tablet PC comes with a 13.1in screen, weighs 3.7 pounds and is priced starting at $1,670 (£840).

The laptops run on Intel Core 2 Duo low-voltage or ultra-low voltage processors, include up to 8GB of RAM and support Wi-Fi and Bluetooth. Storage options include hard drives or 80GB solid-state drives. The laptops come with Intel's integrated graphics technology.

Running Microsoft's Windows Vista OS, users will have the option to downgrade to Windows XP. The laptops will be available worldwide, according to the company.