Hello mahesh, For an exposed MS Structures we usually suggest a first coating of zinc chromate paint which makes the steel rustfree though regular maintenance is needed ..on top of this you will have to paint with your desired colour paint either matte or glossy as per your preference. If that s already painted and the rusted, completely remove and scrap of the paint before you apply zinc chromate paint. Hope our answer helped your query do contact us for professional help
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