EN14399 3 High strength bolting assemblies for preloading- part 3 - system HR hexagon bolt and nut assemblies HR Cl. 10.9/10 + 2 plain chamfered washers EN 14399 6 K2 HDG Cert. 3.1 M20x100mm, 5600 pz. M20x095mm, 5950 pz. M20x080mm, 3950 pz. M20x070mm, 3150 pz. M24x065mm, 3300 pz.