Aluminum square tube (U type side pass, U slot) is one of the last few years the production of ceiling materials, aluminum Fangtong with open eyes, ventilation, ventilation, the crisp lines neatly structured, embodies the modern style concise, easy and convenient installation and disassembly, become the main products in recent years, the wind extravagant decoration market. For hidden projects, a large number of crowded public places, easy to air circulation, exhaust, heat dissipation at the same time, can make the distribution of light evenly, so that the whole space is spacious and bright. It is widely used in subway, high-speed rail station, station, airport, shopping mall, passageway, leisure place, public toilet, building exterior wall and other open places.