Cable channel is a fully closed cable tray. The difference from the tray on the concept is that the ratio of height and width is different. The tray is shallow and wide, and the cable channel has a fixed depth. It is most suitable for laying computer cables, communication cables and control cables and other cables with low heat. Metal box wiring can make weak electric cable free from the disturbance of strong electric line, the cable can get good protection from damp and corrosive environment by plastic box wiring.