Features:Made of fine stainless steel material ,not easy to rust. The serrated design makes the gasket more tight and not easy to slip.The set includes 8 kinds of washer of different sizes to meet your different needs.They are integrated in a box,portable and convenient to access and store.Accurate design, wear resistance, high reliability.The bearing clip, which is the bearing retainer ring, is a type of hole movement on the slot shaft for fixing the components. The inner diameter of the retaining ring is slightly smaller than the inner diameter of the mounting shaft.The circlip pliers must be used for installation. Insert the jaws into the caliper holes of the retaining ring and expand the retaining ring to insert into the pre-machined shaft groove.Specification:Item Type:Serrated Lock WasherMaterial:304 Stainless SteelPackage List:50PCS External Serrated Lock Washer M2.550PCS External Serrated Lock Washer M350PCS External Serrated Lock Washer M440PCS External Serrated Lock Washer M540PCS External Serrated Lock Washer M630PCS External Serrated Lock Washer M820PCS External Serrated Lock Washer M1020PCS External Serrated Lock Washer M12