The Japanese were approached for a design of cruiser to match the new ships being built for the other South American countries. The Japanese designers not being restrained by treaty considerations as its US and European competitors were, decided to overmatch the ships they new of. A main armament of eight 10" guns in a new configuration compared to earlier models was fitted, while the rest of the design conformed with the standard heavy cruiser configuration. This was done to confuse Allied observers who kept a close eye on the Japanese shipbuilding industries. Having a bigger ship to play with the designers made use of this by fitting more belt and deck armour than the smaller cruisers.
Displacement: 16,000 tons standard, 21,500 tons full load
Dimensions: 663 x 76 x 24 feet
Machinery: 4 shaft geared Kanpon turbines, 150,000shp
Speed: 33 knots
Endurance: 8,000 miles at 20 knots
Armour: 7" belt, 3" deck, 6" turrets
Armament:
8 x 10" (4x2)
8 x 5" (4x2)
42 x 25mm (10x3 12x1)
Torpedoes: 12 x 21" (4x3)
Aircraft: 3
Complement: 1100