These 4.7" guns were an evolution of previous anti-aircraft guns, and were intended for installation on the cancelled G3 Battlecruisers. The they were later mounted on the HMS Nelson and Rodney in open mounts, which were later enclosed by the time of World War Two. These guns also saw service aboard the Courageous class aircraft carriers, and HMS Adventure and HMAS Albatross.

Standard Master Model installation instructions.