These washers are made of 304 stainless steel on one side with high hardness, corrosion protection and rust protection. which means that even outdoor use as well as in damp areas is no problem. The other side is neoprene EPDM, which has the properties of ageing resistance, resistance to high and low temperatures, acid and alkali resistance. Washers made of bonded neoprene (also known as sealing discs and damping discs) are special washers that ensure an airtight seal between the bolt or the screw and the hard surface. Waterproof sealing discs are smooth, hard and thick. They are well-suited and compatible with self-drilling screws, and are often used in electrical appliances, industrial machinery, as well as residential and commercial construction. .
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