... frame of lamp board is made of high-quality steel, hot-dip galvanized 5.Mode of switch: hand control,time control ... ,Stations,Ports,Airports,Stadiums, Highways,Container yards,Parks Town square,railway stations,docks,freight yard,highways,stadiums,flyovers,etc. ... by Hot dip galvanized preservative treatment2.the use of high-quality stainless steel skeleton3.fasteners bolts, stainless steel nut ...