The Koster-class is a class of five Mine-countermeasure vessels currently in use by the Swedish Navy. Built originally between 1982-1993 as part of the seven-strong Landsort-class mine countermeasures vessels the last five ships of the class were given a comprehensive midlife upgrade between 2007-2010 which resulted in HMS Koster becoming the lead-ship of the newly upgraded class of MCMVs. After the upgrade the Swedish Navy expects that it will serve on for another 15-20 years. Given a list of categories: company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, what category does the paragraph belong to?
A:
Mean Of Transportation