Fast Patrol Boat (FPB)

A high-speed patrol craft, typically 100 to 400 tonnes and capable of 25 to 40 knots, used for coastal interdiction, intercept, and constabulary boarding. The FPB designation covers both lightly armed law-enforcement hulls and gun- or missile-armed military variants; Lurssen’s FPB series is a well-known commercial family. An FPB armed with anti-ship missiles overlaps the fast-attack-craft and missile-boat categories, while a gun-only variant stays in the patrol-boat constabulary role.