Discover the precision of naval history with the GUN BOAT PGM-9 Class Motor Gunboat 3D model. This detailed model represents the versatile PGM-9 class used by the Greek Navy, showcasing their significant modifications and roles during and post-World War II. Names and Service Years. Historical Context: During WWII, PGMs operated with PT boats but later proved more effective with minesweepers. These vessels were armed with a range of weaponry, including a 3? /50 gun, 40mm bofors, 20mm guns, twin. 50 caliber machine guns, and a 60mm mortar.