Spring Lock Washer Conical Black-Phosphate for M16 Screw 17 mm ID, 3PK

The arched shape of these washers presses up against a bolt and down against a nut to prevent loosening from wear vibration or temperature changes. Similar to a spring they flatten out as pressure is applied helping to absorb shocks. They grip bolts more tightly than split and tooth lock washers. Unlike Washers which can only be tightened in one direction these washers have a continuous body that can rotate in either direction.Conical and curved washers are functionally the same and are often referenced using their DIN specifications. These DIN specifications refer to slight differences in OD and thickness. DIN 6796 is the standard for conical spring lock washers which are also known as Belleville washers.Steel washers are stronger and more wear resistant than zinc-plated steel and stainless steel. They are best for dry environments since moisture will cause them to rust. Similar to zinc plating washers with a black phosphate coating are protected from rust in wet environments. They have a black finish that blends in with dark surfaces.