The above screws can have both plain and spring washers together for class 8.8 and above combination screws, the screws are first heat treated separately, the washers are assemled and thereafter the threadin operation is carried out on the hardent shank. For all such screws hydrogen de-embittlement operation is performed after surface treatment.
||: M4 to M12 (10mm to 60mm length)
||: As per customer spec
|| : 6.8, 8.8, 10.9