The 18-pounder was a quick-firing horse-drawn field gun designed to be towed behind a limber and six horses. The gun barrel was wire-wound nickel-steel with a single-motion screw breech with a cartridge extractor. It fired a fixed round of shell and cartridge fixed together, which was known as "quick firing" in British terminology. The lower carriage comprised a single hollow steel trail fixed to the centre of the axle-tree. The limited traverse saddle supported the elevating mass and a shield. Traverse controls were on the left and elevation on the right of the saddle. Recoil was by a hydraulic buffer with telescopic running-up springs to return the barrel to its firing position.