Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. USS Lookout (YAGR-2) -  USS Lookout (YAGR-2/AGR-2) was a Guardian-class radar picket ship acquired by the U.S. Navy in 1954. She was reconfigured as a radar picket ship and assigned to radar picket duty in the North Atlantic Ocean as part of the Distant Early Warning Line.
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Mean Of Transportation