These Forgefix Form B Flat Washers are Zinc Plated for increased resistance to corrosion Washers provide a smooth surface for the nut or bolt to bear on making it less likely to loosen as a result of an uneven fastening surface The main purpose of a washer is to distribute the load under a bolt head or the nut face APPLICATIONOn all manner of bolting applications Can be used with all types of bolts & nuts Zinc coatings prevent oxidation of the protected metal to create a longer lasting finish It does this by forming a barrier & by acting as a sacrificial anode if this barrier is damaged Zinc oxide is a fine white dust that in contrast to iron oxide does not trigger a breakdown of the substrate’s surface integrity as it is formed The zinc oxide if left intact can act as a barrier to further oxidation in a way similar to the protection afforded to aluminum & stainless steels by their oxide layers