The matching bolt and nut grades identifying markings are designated differently to demonstrate the strength relationship of the two components. Due to the advent of mass assembly it is an acceptable practice for the matching nut to be the stronger component. The logic behind this theory is that during assembly if the nut is stronger the joint should fail immediately and thus reduce subsequent field failures. More specific information as to this relationship can be found in Section 10 of our catalog on pages 10-1020 and 10-1021.