This document belongs to the suite of European Standards EN 14399 and is designed to be read in conjunction with EN 14399 -1 for:- general requirements;- testing for conformity evaluation;- evaluation of conformity;- regulatory marking;for assemblies of high-strength structural fit bolts and nuts of system HV suitable for preloaded joints with, thread sizes M12 to M36 and bolt property class 10.9 and EN 14399-2 for suitability testing.This part gives requirements for:- dimensions;- associated washer(s) according to EN 14399-6;- performance and suitability testsfor assemblies with thread sizes M12 to M36 and bolt property class 10.9.Assemblies of hexagon fit