Like other British flotilla leader designs, these ships were significantly larger than the typical destroyers of the day, in order to accommodate the flotilla staff ("Captain (D)" in Royal Navy parlance) and the necessary additional signalling gear. All ships had four funnels, the foremost being taller (although it was later cut down post-war in Nimrod and Abdiel). They were armed with four QF 4 inch guns. The guns were carried one each on the forecastle, between the first three funnels and on a bandstand on the quarterdeck. Abdiel and Gabriel were later fitted as fast minelayers, for which purposes they landed the after 4 inch gun and their torpedo tubes and were screened by canvas panels from the fourth funnel to the stern to give shelter to 60 to 70 mines. Nimrod and Kempenfelt later received QF 12 pdr (3 inch / 76 mm) 18 cwtanti aircraft guns in place of one of the QF 2 pdr.
Following the war-time trend to install director firing in ever-smaller vessels as resources permitted, Lightfoot was selected to serve as a test-bed for the Royal Navy's new training-only director firing system for flotilla leaders and destroyers in March, 1917. By August, results obtained were favourable enough that it was decided to equip fully 203 other leaders and destroyers of "L" class and later.