Grade 5 (Inch) & Class 8.8 (Metric) Hex Cap Screws

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Grade 5 and 8.8 hex cap screws are medium-strength carbon steel fasteners designed for reliable connections in the automotive and machinery industries. These hex head bolts feature a six-sided head for secure tightening and are available in both full thread and partially threaded shafts.

Fasteners Etc., Inc. offers these high-quality hex head cap screws in a variety of finishes, including zinc plated, zinc yellow, and plain steel. Whether you are securing frames with heavy hex nuts and flat washers or sourcing a specific SKU for a production pkg, we have the inventory you need. Explore our full catalog of hex cap screws or visit our fasteners department for additional hardware. Contact us today for expert assistance!

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Key Features and Differences: Grade 5 and 8.8 Hex Cap Screws

Grade 5 Hex Cap Screws

We supply Grade 5 hex cap screws designed to meet ASME B18.2.1 industry standards and have a minimum tensile strength of 120,000 psi. These screws, made from medium-strength steel, are available with plain, zinc, or zinc yellow platings to suit a variety of applications. These fasteners receive additional strength through heat treatment, making them ideal for medium-strength applications. Standard and USA Grade 5 hex cap screws are easily identified by three lines on the bolt head.

Class 8.8 Hex Cap Screws

Class 8.8 hex cap screws are the metric equivalent of Grade 5 screws, offering similar strength and performance. Our selection of Class 8.8 screws includes plain and zinc plating options available in both DIN and ISO standards for various project demands. Like Grade 5 screws, these fasteners are heat treated for extra strength and have a minimum tensile strength of around 120,000 psi.

Applications of Grade 5 and Class 8.8 Hex Cap Screws

While Grade 5 and Class 8.8 hex cap screws utilize different measurement systems (Imperial vs. Metric), they share a similar tensile strength and are used across various medium-duty industries. These fasteners are engineered for durability in environments where vibrations and moderate loads are common.

Common applications include:
  • Automotive: Securing critical engine components, suspension systems, and drivetrain assemblies.
  • Military: Assembly of combat vehicles, transport equipment, and heavy weapon mounts.
  • Machinery: Constructing rigid equipment frames, gearboxes, and industrial housings.
  • Industrial Manufacturing: Joining structural frameworks and mounting production line systems.
Whether you need zinc plated bolts for corrosion resistance or carbon steel for internal assemblies, these hex head cap screws provide the reliable holding power required for high-stress trade applications.

Choosing the Right Hex Cap Screw for Your Needs

When selecting a fastener for your application, you must consider factors like load requirements, material compatibility, and environmental elements. Hex cap screws are available in a range of grades, from Grade 2 to Grade 8 to stainless steel and more. Each grade is designed for specific uses, so be sure to understand your project needs before choosing a screw. If your application requires medium-strength fasteners, Grade 5 or 8.8 hex cap screws may be your best option—and choosing between those screw variants will be based on whether your project uses imperial or metric measurements.
Additionally, the materials you use and the environmental conditions of your application will help you determine whether your fastener will require special plating. Contact us with any questions, and our team will help you choose the right hex cap screw for any project.

Your Trusted Grade 5 & 8.8 Hex Cap Screw Supplier

At Fasteners Etc., Inc., we proudly provide high-quality industrial fasteners for a variety of projects and industries. With a wide selection of hex cap screws, our inventory offering is carefully curated to ensure we can provide you with precisely what you need. Our team of experts is highly trained and prepared to assist you with any questions or concerns. Contact us to learn more, or request a quote today to begin your order.
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