5/16 Stainless Steel Finishing Washers FAS Cup Countersunk 25pcs

Description

Product Overview

The 5/16 stainless steel finishing cup washers from FAS are engineered to meet the demanding requirements of industrial and scientific applications. Constructed from premium 18‑8 stainless steel, each washer offers exceptional corrosion resistance, ensuring long‑term reliability even in harsh environments. The countersunk design provides a flush finish that eliminates protrusion, reducing the risk of snagging or interference with moving parts. Each washer is precision‑machined to tight tolerances, guaranteeing a consistent inner diameter that matches standard fastener sizes for a secure, snug fit.

These cup washers are supplied in a lot of 25 pieces, each individually sealed in resealable bags to protect against moisture, dust, and contaminants during storage and transport. The packaging process includes a rigorous shipping audit and quality control inspection, confirming that every washer meets the exact specifications before it reaches the customer. The result is a product that delivers both performance and peace of mind, backed by FAS’s reputation for quality and reliability.

Usage

Designed for a wide range of applications, these cup washers excel in machinery assembly, equipment maintenance, and prototype development. They are ideal for securing bolts, screws, and threaded rods in automotive, aerospace, and heavy‑industry settings where a low‑profile finish is essential. The countersunk shape allows the fastener head to sit flush with the surrounding surface, preventing snagging on cables or moving components.

Because of their stainless‑steel composition, the washers perform reliably in environments exposed to moisture, chemicals, or temperature fluctuations. Whether used in outdoor installations, marine equipment, or clean‑room facilities, they maintain structural integrity and resist rust formation. The resealable packaging also makes them convenient for on‑site inventory management, allowing technicians to quickly access the exact number of washers needed for each job.

Why Choose Us

FAS stands out as a trusted supplier of high‑quality fasteners and related components. Our cup washers undergo a multi‑stage quality assurance process that includes material verification, dimensional inspection, and functional testing. Each batch is lot‑controlled, ensuring traceability and consistency across shipments. The QC‑inspected status guarantees that every washer conforms to the specified 5/16 size and countersunk profile, eliminating the need for re‑work or adjustments during assembly.

In addition to product excellence, we provide responsive customer support and after‑sales service. Our technical team is available to answer questions about compatibility, installation best practices, and any custom requirements you may have. We also offer flexible ordering options, allowing you to purchase the exact quantity you need without excess inventory.

Key Features

• Premium 18‑8 stainless steel delivers superior corrosion resistance for long‑lasting performance.
• Countersunk design ensures a flush finish, reducing snag risk and improving aesthetic integration.
• Precision‑machined dimensions provide a reliable, snug fit for standard 5/16 fasteners.
• Resealable bag packaging protects against moisture and contaminants, extending shelf life.
• Dedicated customer support and warranty coverage for peace of mind after purchase.

FAQ

What size fasteners are these cup washers compatible with?

These washers are sized for 5/16 inch diameter fasteners, which corresponds to standard #10‑13 bolt and screw sizes commonly used in industrial applications.

Are the washers suitable for outdoor or marine environments?

Yes. The 18‑8 stainless steel construction provides excellent resistance to rust and corrosion, making them appropriate for outdoor, marine, and other moisture‑exposed settings.

How many washers are included in each package?

Each package contains 25 individually sealed cup washers, packaged in resealable bags to maintain cleanliness and protect against environmental factors.

Can I request a different quantity or custom packaging?

FAS offers flexible ordering options. Contact our sales team to discuss bulk orders, custom lot sizes, or alternative packaging solutions that meet your project needs.

What quality standards do these washers meet?

All washers are QC inspected and meet industry standards for dimensional accuracy, material composition, and performance, ensuring reliable operation in demanding applications.