1,Plastic pneumatic fittings. 2,Elbow type. 1, Brass with good nice nickel plated.2, BSPT thread (British Standard ... any other seal material.6,Bottom was hexagonal suitable for fitting by lkey.7,Chipware is zinc.8,Inner seal can ... degree9,The snap spring is stainless steel with heat treatment and the life time is more than 1000 times.