HMS C2 was one of 38 C-class submarines built for the Royal Navy in the first decade of the 20th century.

[1] For surface running, the boats were powered by a single 16-cylinder 600-brake-horsepower (447 kW) Vickers petrol engine that drove one propeller shaft.

On the surface, the C class had a range of 910 nautical miles (1,690 km; 1,050 mi) at 12 knots (22 km/h; 14 mph).

They could carry a pair of reload torpedoes, but generally did not as they would have to remove an equal weight of fuel in compensation.

During World War I, the boat was generally used for coastal defence and training.