This part of ISO 6149 specifies dimensions, performance requirements and test procedures for metric adjustable and non-adjustable light-duty (L series) stud ends and O-rings. Stud ends in accordance with this part of ISO 6149 may be used at working pressures up to 40 Mpa [400 bar1)] for non-adjustable stud ends and 31,5 MPa (315 bar) for adjustable stud ends. The permissible working pressure depends upon the stud end size, materials, design, working conditions, application, etc. Conformance to the dimensional information in this part of ISO 6149 does not guarantee rated performance. Each manufacturer should perform testing according to the specification contained in this part of ISO 6149 to assure that components comply with the performance ratings.