Please answer the following question: 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. Purga-class icebreaker - The Purga class are a group of icebreaker Patrol ships operated by the Russian maritime border guard. The Project 22120 patrol ship Purga (encode blizzard) is a new generation border patrol vessel. Originally founded as a big revenue cutter. Vessel has ice strengthening providing independent navigation in a rarefied one-year ice thickness up to 0.6 m in winter and spring to navigate and up to 0.8 m thick in summer and autumn navigation.
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Mean Of Transportation