Spring lock washer: This kind of spring washer is standard parts. It is made according to the GB7244, , we can produce from the size M2-M42, the Material of it on the pic is steel, , the finishment of it is white galvanized, the material can be stainless lteel, steel or copper. We also can make DIN128, DIN7980, ASME, JIS and other standards or unstandards.