These Forgefix Flat Penny washers, have a 25mm outside diameter. The washers are bright zinc plated for increased corrosion resistance, & have been given the name ' Penny Washer' due to their similarity in size to an old penny. 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. Application: On all manner of bolti