2 × 18 inch external-traversing torpedo tubes forward of the conning tower
1 x 75 mm gun
1 x 12.7 mm machine gun
The K III class was a class of two patrol submarines, built by Koninklijke Maatschappij De Schelde in Vlissingen for the Royal Netherlands Navy. They were used for patrols in the Dutch colonial waters. The submarines' diving depth was 40 metres (130 ft). The design for the double-hulled boats came from the American Electric Boat Company.