suitable for carry all kinds of ceiling.(use above the triangle keel or strip keel), It can adjust level. Thinkness: 0.34mm,0.45mm Length: 3000mm, 6000mm, or any length you order. Please contract us immediately. Our website for main keel,is /bs/exhibition.php?page=&id=004&mode=cn&filterproduct=3&difurl=51a6a4e249b88c7e43e09ce6cbb73233 Origin china Material galvanized steel