A NEXUS border crossing card is a form of identification that people use to cross the border between Canada and the United States, according to the Department of Homeland Security. The cards are presented at designated processing lanes and kiosks at NEXUS-approved air, land and marine ports of entry.
NEXUS cards are issued as part of a prescreening border crossing program, which allows for expedited processing for people wishing to enter the United States and Canada, explains U.S. Customs and Border Protection. Cards are available to U.S. and Canadian citizens and lawful permanent residents who meet certain eligibility guidelines. Individuals under the age of 18 must have the consent of a parent or legal guardian to be eligible.