The RadSeeker is a new hand-held radiation detector from Smiths Detection of Danbury, Connecticut. The compact unit can identify radiological and nuclear threats for applications including search operations, border vehicle screening, and cargo security. The device offers greater speed and accuracy in detecting and identifying threat materials, including masked and shielded special nuclear materials. It is designed to withstand impact as well as extreme temperatures and weather conditions. It meets the requirements of the ANSI N42.34 (2006) performance standard and the U.S. Department of Homeland Security Domestic Nuclear Detection Office, and it has passed extensive government and laboratory testing.