[3] Three Thornycroft boilers fed steam to two triple expansion steam engines rated at 5,000 indicated horsepower (3,700 kW) and driving two propeller shafts, giving a design speed of 30 knots (56 km/h; 35 mph).

Sufficient oil was carried to give a range of 330 nautical miles (610 km; 380 mi) at 25 knots (46 km/h; 29 mph) or 2,200 nautical miles (4,100 km; 2,500 mi) at 9 knots (17 km/h; 10 mph).

The ships' armament was changed at the same time, to four 76 mm/40 guns and two 450 mm (18 in) torpedo tubes.

[9] They were fitted for minelaying, with a capacity of 10–16 mines during the First World War, during which three destroyers were lost.

[3] Following the end of the war, the remaining three ships had a boiler removed, with the consequent loss of a funnel, together with a 76 mm gun, and were reclassified as torpedo boats.