ribbed stainless steel screws with wafer head

EPDM washered fasteners are specialized fastening solutions that incorporate EPDM washers as sealing components. EPDM is a synthetic rubber renowned for its excellent resistance to weathering, ozone, ultraviolet (UV) radiation, and various chemicals. When integrated with fasteners, EPDM washers enhance the performance of bolted joints by providing effective sealing, reducing the risk of leaks, and accommodating thermal expansion and contraction.


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A 3 8 full threaded rod, often referred to as a fully threaded screw or all-thread, is a long, cylindrical object with threads running along its entire length. The 3 8 in the name refers to the material grade, which typically signifies a stainless steel alloy, specifically Type 308. This grade is renowned for its excellent corrosion resistance and high-temperature strength, making it ideal for use in environments prone to rusting or where heat resistance is crucial.

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The black coating on these screws adds an additional layer of utility. Typically, this coating is a form of zinc plating or a powder coat finish, which serves two primary purposes. Firstly, it enhances the screw's corrosion resistance, protecting it from rust and wear, especially in outdoor or humid conditions. Secondly, the black color offers a sleek, unobtrusive appearance, making it suitable for applications where a discreet fastener is desired.

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