The class were intended to be armed with ten 5.25-inch (133 mm) guns in five twin turrets, which were of the same circular design as the secondary armament in the s. A shortage of the guns, due to difficulties in manufacturing them, led to the first group being armed with only eight 5.25-inch guns in four twin turrets. The fifth twin turret was added later to only. The first group was also armed with a gun for firing star shell and two quadruple QF 2-pounder (40 mm) "pom-poms".