A C-Purlin is a structural steel member shaped like the letter “C.” It is widely used in construction for supporting roofs, walls, and other structural elements. The “175x75x16mm” specification refers to its dimensions – a depth of 175mm, a flange width of 75mm, and a thickness of 16mm. The galvanization process involves coating the steel with a layer of zinc, which provides superior protection against rust and environmental damage.