 All "30 knotter" vessels with four funnels were classified by the Admiralty as the B class in 1913 to provide some system to the naming of HM destroyers.Fourteen vessels were built by Laird Brothers at Birkenhead (in 1903 to become part of Cammell Laird, Birkenhead), seven by Palmers Shipbuilding and Iron Company at Hebburn-on-Tyne, and one each by Armstrong Whitworth at Walker-on-Tyne, William Doxford and Sons at Sunderland, and J & G Thomson (later to become John Brown and Company) at Clydebank.All vessels had a distinctive "turtleback" forecastle that was intended to clear water from the bow, but actually tended to dig the bow into anything of a sea, resulting in a very wet conning position.