Definition: Adjustable end is male thread stud, it consist of locknut, back-up washer, o-rings and retaining ring. DIN fittings is standard end of 24 deg cone connector and cutting ring fittings to connect steel pipe, adapters or hose assembly, adjustable stud fittings are commonly found on Elbow, Tee and Cross Fittings to allow for proper orientation of the fittings.Methods of adjustable stud end: It will be assembled with a locknut, back-washer, sealing by O-ring or O-ring+Retaining Ring. There are four standards of sealing port as follows:Metric thread + O-ring + Retaining O-ring (ISO 9974)Metric thread + O-ring ISO 6149UN/UNF thread + O-ring ISO 11926 SAE J1926 ORBBSPP thread + O-ring + Retaining Ring (ISO 1179)Burst and cyclic endurance(impulse) tests shall be conducted in according with ISO 19879.Dimensions, working pressure, performance, flatness and fit of adjustable studs end washers, O-rings, designations of stud ends, please contact us by email.