Most of the fasteners have a coating. This can be a zinc, copper, chrome or paint coating or a galvanisation. Some coatings give a better rust protection than others.
In case the fasteners are used in all weather conditions or by example salt water, it is recommandable to use fasteners made of stainless steel (ss). It is often thought that stainless steel is harder than ordinary steel, but it this is based on a misunderstanding. It is even a little bit softer.
Fasteners of Stainless steel are often used for sustainable building. In the coastal regions, where fasteners, beside the normal weater influences, also have to deal with the salt from the seawater, it is also advised to use stainless steel fasteners.
