... , easy building and air clean room as walls, ceilings. Core Materials Options:Polystyrene(EPS), Polyurethane(PU), and RockwoolType one: ... Sandwich panel *Rockwool is featured with the best fire-resistance among three types of core materials, and with more heat & sound insulation ... for inflammable products etc.Connection Types:1.Wall Panel:Connection with H Bar, Self-insert Connection2.Roof Panel: Bolt- ...