Zinc primer is a spray-on coating that goes on before the powder-coating process. Zinc rich primers are unique from regular primers because they contain zinc which has highly sacrificial anodic properties. High concentrations of zinc dust act sacrificially when in direct contact with steel by providing cathodic protection and galvanizing properties. Simply put, the zinc primer provides a secondary layer of protection. This is an extra measure to help prevent any corrosion that the typical powder-coating (without a zinc primer) may not provide during ordinary conditions over time. However, because zinc primer is a spray on coating, it can be scratched or nicked just like paint.