DescriptionGRP Engineering Head Studs are made right here in Australia from AISI H-13 Tool steel and once machined all studs are heat treated to 38-42 Rockwell C scale. Kit includes4 x M11 GRP Engineering H-13 Studs, 4 x ARP M11 Nuts and 4 x ARP M11 Washers Torqued to 80ft/lbs4 x M12 GRP Engineering H-13 Studs, 4 x ARP M12 Nuts and 4 x ARP M12 Washers Torqued to 90ft/lbs
