 All were powered by triple expansion steam engines for and had coal-fired water-tube boilers, except for the final vessel ("Stag") in which the engine power was slightly raised to .Armament was one QF 12-pounder gun on a bandstand on the forecastle, five QF 6-pounder guns (two sided abreast the conning tower, two sided between the funnels and one on the quarterdeck) and two single tubes for 18-inch (450 mm) torpedoes.Due to the successful development of their previous 26 and 27-knot torpedo boat destroyers, John I Thornycroft & Company developed their two funnel design for the 1894/1895 – 1897/1898 building programs.