EN 14399-10 1 High-strength structural bolting assemblies for preloading - Part 10: System HRC - Bolt and nut assemblies with calibrated preload, with 1 washer Hot dip galvanized steel M16x45, 410 pcs. M16x50, 180 pcs. M20x55, 560 pcs. M20x60, 375 pcs. M20x65, 110 pcs. M24x70, 85 pcs.