Washers

  • Washers

Washers sit under a bolt head or nut to spread the clamp load and protect the work surface. The right washer protects the joint, spreads the load, and keeps the fastener from working loose over time. South Coast Fasteners stocks Washers in a full range of sizes, grades, and finishes, with fast 3-5 day shipping.

Materials and Sizing

Washers come in steel, hardened, and stainless options, plain or zinc and hot-dip galvanized for corrosion resistance. Sizing follows the bolt or screw diameter they seat under, so the bearing surface lands flat and spreads the load evenly. Pair them with Bolts and Finished Hex Nuts to complete the assembly.

How to Choose

Size the washer to the bolt or screw it seats under, then pick a material and finish that match the joint. Use hardened washers under high-strength fasteners and stainless where corrosion is a concern.

Applications

Washers are used under bolt and nut assemblies in structural, mechanical, and general fabrication work across Construction, Manufacturing, and Automotive. Our washers selection is stocked for quick turnaround, in both bulk and smaller pack quantities, so the right size is ready when you need it.

What are washers?

Washers are flat or shaped rings that spread load, protect surfaces, or lock a joint, including flat, fender, structural, lock, and sealing washers.

What are washers used for?

Use a flat washer to spread load, a fender washer for thin or oversized holes, a structural washer under high-strength bolts, and a lock washer to resist loosening.

What is the difference between USS and SAE washers?

USS flat washers are larger for heavy bolting and SAE washers are smaller for a tighter fit, while hardened structural washers go under high-strength bolts.

Please contact us for assistance in selecting the right product or placing an order.


At South Coast Fasteners, we offer a range of washers tailored to meet the demands of industries ranging from construction and manufacturing to automotive and marine. Whether you need heavy-duty structural washers or corrosion-resistant stainless steel options, our selection delivers the strength and precision your projects require.

Types of Washers

Structural Washers

Structural washers, sometimes called heavy-duty washers, are made for applications where maximum strength is essential. With a thick profile and larger outer diameter, they spread loads over a wide surface area, reducing the risk of bolt failure or surface damage. They are the Standard choice in construction, bridge building, and infrastructure projects where fasteners must endure extreme stress without compromise.

Within this group of washers, F-436 washers provide thru-hardened strength for structural steel connections, while DTI squirter washers add a visual confirmation of proper bolt tension for compliance and safety in critical builds.

Flat Washers

Flat washers are the most widely used washer type. Simple in design yet critical in function, they protect surfaces and spread load evenly to prevent fastener damage or loosening. Available in multiple sizes, thicknesses, and materials, flat washers are found everywhere from furniture assembly to heavy machinery, proving their flexibility across industries.

Flat washers include USS flat washers with their larger diameters for heavy-duty jobs, SAE flat washers with tighter tolerances for automotive and precision work, and fender flat washers with oversized diameters to reinforce softer or thinner materials like sheet metal, wood, and plastics.

Thru-Hardened Flat Washers

Thru-hardened flat washers are heat-treated for higher hardness and strength. This added toughness allows them to resist deformation under heavy loads, making them good for tough applications in automotive manufacturing, heavy equipment, and industrial assembly.

Both USS and fender washers are available in thru-hardened varieties, offering additional durability for jobs where pull-through resistant and surface protection are critical under extreme stress.

Stainless Steel Washers

Stainless flat washers, lock washers, and fender washers provide corrosion resistance and long-term durability, even in aggressive environments. Common in marine construction, food processing plants, and outdoor projects, stainless washers are where rust resistant and clean performance are required. Grades like 18-8 and 316 helps keep flexibility for both general use and specialized conditions.

This family of washers also includes AN960 and MS15795 washers built to military Standards for aerospace, NAS620 washers manufactured to National Aerospace Standards for extreme precision and strength, and bonded neoprene sealing washers that combine stainless steel with a neoprene backing to create airtight and watertight seals.

Lock Washers

Lock washers are engineered to prevent loosening caused by vibration and torque. With split or toothed profiles, they create tension that locks fasteners in place, making them indispensable in machinery, equipment, and structural assemblies that face constant movement or stress.

Round Plate Washers

Round plate washers provide more load distribution than Standard flat washers thanks to their larger outer diameters. They are commonly used in timber construction and framing, where preventing pull-through in softer materials is to structural stability.

Round Malleable Washers

Round malleable washers are made from ductile iron, which allows them to conform to irregular or uneven surfaces. They are used in fencing, railroad construction, and timber applications where strength is necessary but flexibility and adaptability are also important.

Square Washers

Square washers resist rotation during tightening and spread load across a wide surface. They are often used in wood or softer materials where round washers might embed themselves. Their shape provides additional stability in framing, decking, and structural wood applications.

Countersunk Finishing Washers

Countersunk finishing washers, also called cup washers, are used with countersunk screws to create a flush, finished appearance. They conceal screw heads and provide a smooth surface, making them popular in woodworking, cabinetry, furniture, and architectural detailing where aesthetics matter.

Shear Plate Washers

Shear plate washers, or timber connectors, are heavy-duty washers built for timber construction. With serrated or toothed surfaces, they grip into wood to distribute loads and resist slipping. They are used in bridge building, decking, and heavy framing where strength and longevity are critical.

Nylon Washers

Nylon washers are lightweight, non-conductive, and chemically resistant. They provide cushioning, electrical insulation, and vibration resistant, making them good for automotive, plumbing, and electrical work. Their flexibility makes them a strong choice where metal washers would be too rigid or heavy.

Silicon Bronze Washers

Silicon bronze washers combine corrosion resistance with strength, making them the top choice for marine and coastal applications. They are also valued in architectural and decorative uses where appearance is important. Over time, they develop a natural patina that adds to their character without sacrificing performance.

Washers Industry Applications

Washers is essential in nearly every industry and environment. In construction, they secure beams, trusses, and steel connections for structural integrity in buildings and bridges. Manufacturing relies on washers to protect machinery, distribute loads in assembly lines, and prevent costly failures. Automotive and aerospace industries depend on precision washers like AN960, MS15795, and NAS620 to withstand vibration, torque, and high-performance demands.

Marine and offshore operations require corrosion-resistant stainless washers, fender washers, and neoprene-bonded sealing washers that hold up against constant saltwater exposure. Even in everyday home improvement, washers are the unsung heroes that make it possible to mount shelves, secure furniture, and install fixtures with confidence. Whatever the project, washers from South Coast Fasteners add strength, stability, and confidence.

Frequently Asked Questions

What types of Washers does South Coast Fasteners carry?

We stock Structural Washers, Flat Washers, Thru-Hardened Flat Washers, Stainless Steel Washers and Lock Washers. Each is kept on the shelf and ships fast in standard sizes.

What are Washers used for?

Washers are commonly used across Automotive, Construction, and HVAC for secure, fastening.

Can I order Washers in bulk or request a quote?

Yes. We stock Washers for both small orders and full production runs. Reach out for a quote or product help.

Why Choose South Coast Fasteners?

South Coast Fasteners covers fasteners, PPE, hand tools, cutting tools, abrasives, and industrial supplies, kept in stock and priced to undercut the national suppliers.

Shop Washers Online at South Coast Fasteners

South Coast Fasteners stocks a full range of materials, standards, and sizes suited for tough applications. From flat and lock washers to structural, fender, and sealing variants, our inventory covers the washer types relied upon across construction, manufacturing, and mechanical assembly to distribute load, prevent loosening, and protect mating surfaces. With competitive pricing and fast shipping, we are your source for washer solutions.