The purpose of this test is to evaluate the axial strength of the nut seat of wheels intended for use on passenger cars@ light trucks@ and multipurpose vehicles. In addition@ a minimum contact area is recommended to ensure enough strength for the rotational force in tightening a nut against the nut seat. While this test ensures the minimum strength of the nut seat@ the wheel must also have a degree of flexibility. This flexibility@ as well as bolt tension@ are important to maintain wheel retention.