The U.S. Department of Homeland Security has ordered additional RadSeeker handheld radiation detectors and identifiers from Smiths Detection Inc.

RadSeeker is a self-stabilizingradiation detection and identification system used by DHS, U.S. Customs and Border Protection, emergency responders and law enforcement agents around the world.

"Our cutting-edge RadSeeker technology was developed in cooperation with DHS to meet specific requirements to help keep our country safe from the threat of nuclear and radiological proliferation," said Rob Ledenko, SDI's vice president of North America Sales & Business Development. "We work with our customers to help them apply our reliable, swift and accurate threat detection and identification technology in solutions that address the constantly evolving threats we face around the world."

The RadSeeker task order comes under an indefinite-delivery/indefinite-quantity contract with the DHS Domestic Nuclear Detection Office. It is worth $409 million.

Details on the number of units ordered and a delivery schedule were not disclosed.

SDI said its RadSeeker features the capability to distinguish masked and shielded radiological and nuclear threats from naturally occurring radiation or other legitimate radiological materials.