This is for one package of one hundred (100) quality marine grade stainless steel (AISI 316) SAE 5/16" Flat Washers OD 11/16". Not to be used for overhead lifting. AISI 316 stainless is a premium grade of stainless and is considered by many to be best in class. 316 stainless is corrosion resistant and very durable even in the harshest of conditions. Washers evenly distribute the load of a fastener across a surface and can also be used as spacers, springs, shims, locking devices.