The design provided for 16 gunports (8 per side, excluding the bridle-ports) but one pair was initially left unoccupied, and the ships were always rated at 14 guns.

However an eighth pair of guns was added from 1780 onwards to utilise the vacant ports, without any change in the nominal rating.

They were built just before the Admiralty issued orders that all vessels (especially lesser rates and unrated vessels) should have minimal decoration and carvings to save on costs, due to the seemingly ever-continuing war with France and other nations.

Another five were contracted in November 1775 to be built by commercial shipbuilders (Hound, Hornet, Vulture, Spy and Cormorant), and a further pair during 1776 (Zebra and Cameleon).

Another two were ordered from the Royal Dockyards in January 1777 (Fairy and Nymph) and a final seven from commercial constructors over the following 30 months (Savage, Fury, Delight and Thorn during 1777, Bonetta and Shark during 1778, and Alligator in 1779).