Yes, there are different alloys of stainless steel and yes some are magnetic. But it is error to say the magnetic ones are not stainless steel And yes OMC did use cad plated screws in days of yore—along with stainless screws, depending on their location. Stainless if where they were in plain sight where the customer would raise heck if he saw them rusting. But cad if like under the hood and out of sight because cheaper and actually gave less corrosion of the aluminum. Of course, cad plating was discontinued when somebody discovered cadmium is deadly to people. A thin plating of zinc took their place.
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