supply of precoated galvanised steel sheet roofing accessories 0.50 mm 0.05 total coated thickness zinc coating 120 grams per sqm make tata jindal jsw coloron plus isi or as approved by engineer in charge as per is 277 in 240 mpa steel grade 5 7 microns epoxy primer on both side of the sheet and polyester top coat 15 18 microns etc complete ridges 600mm