British 5,25in (133mm) QF Mark I barrels (16pcs) - King George V, Dido and Vanguard classes Used in King George V battleship class, Dido classes & Vanguard battleship. The set includes turned brass barrels. It is very simple to use in Your model, and makes it extremely realistic. Simply cut off the original plastic barrel and drill a hole in the remaining part and insert the metal barrel using Cyanoacrylate adhesives.