CUSTOMS AND BORDER PATROL Challenge Coin. This is a great looking and colorful CUSTOMS AND BORDER PATROL challenge coin. Coin has reeded edges and is about 1 9/16" in diameter. All details are raised lettering and gold plated. U.S. Customs and Border Protection (CBP) is a federal law enforcement agency of the United States Department of Homeland Security charged with regulating and facilitating international trade, collecting import duties, and enforcing U.S. regulations, including trade, customs, and immigration. CBP is the largest law enforcement agency in the United States. It has a workforce of more than 45,600 sworn federal agents and officers. It has its headquarters in Washington D.C. While its primary mission is preventing terrorists and terrorist weapons from entering the United States, CBP is also responsible for apprehending individuals attempting to enter the United States illegally including those with a criminal record, stemming the flow of illegal drugs and other contraband, protecting United States agricultural and economic interests from harmful pests and diseases, and protecting American businesses from intellectual property theft.