The Japanese called these ships Kaibōkan, "ocean defence ships", (Kai = sea, ocean, Bo = defence, Kan = ship), to denote a multi-purpose vessel. They were initially intended for patrol and fishery protection, minesweeping and as convoy escorts. The ships measured 77.72 meters (255 ft 0 in) overall, with a beam of 9.1 meters (29 ft 10 in) and a draft of 3.05 meters (10 ft 0 in). They displaced 870 metric tons (860 long tons) at standard load and 1,040 metric tons (1,020 long tons) at deep load. The ships had two diesel engines, each driving one propeller shaft, which were rated at a total of 4,200 brake horsepower (3,100 kW) for a speed of 19.7 knots (36.5 km/h; 22.7 mph). The ships had a range of 8,000 nautical miles (15,000 km; 9,200 mi) at a speed of 16 knots (30 km/h; 18 mph).