The BL 5-inch Gun is a British naval artillery piece developed in the early 20th century. It was primarily used during World War I and World War II, serving on various ships, including destroyers and cruisers. The gun is known for its versatility and effectiveness in both anti-surface and anti-aircraft roles. This artillery piece has a caliber of 5 inches (127 mm) and was designed to fire a range of ammunition types, including high-explosive shells. Its reliable performance made it a standard weapon for the Royal Navy, contributing to naval engagements throughout its service life.