Fire Hose Coupling Fire Hose Coupling Fire Hose Coupling Storz, Nakajima & UNI types are made of brass and Barcelona type is made of aluminium. Range of standard coupling sizes for marine use: 1,5’/38 mm, 1 3/4’’/45mm, 2’’/52 mm, 2,5’’/64 mmBrass provides exceptional resistance to harsh marine environment (corrosion, abrasion & sea salt resistance)Impa Code 330871JM, 330851, 330875, 330852, 330872, 330853