This standard specifies the characteristics of heat resisting steel, facing/packing washers for use in non load spreading aerospace applications at temperatures not exceeding 650 °C.They are intended primarily for use as facing/packing washers under the head of bolts with strength classification up to 1 250 MPa to provide adequate clamping of slotted or recessed surfaces (especially on brackets and pipe clippings) and used for adjusting grip lengths of bolts.These washers are not for use in load spreading applications for which EN 3016 washer shall be used.