M3–M6 304 Stainless Steel Conical Countersunk Washers

304 Stainless Steel Bowl-Type Conical Countersunk Washers – M3, M4, M5 & M6

Upgrade your fastening projects with these precision-engineered 304 Stainless Steel Bowl-Type Conical Countersunk Washers. Designed with a distinctive concave-convex fisheye profile, these gaskets deliver superior load distribution, vibration resistance, and a clean flush finish — ideal for both professional and DIY applications.

Available in four popular metric sizes (M3, M4, M5, and M6), these washers are crafted from corrosion-resistant 304 stainless steel, making them suitable for indoor and outdoor use alike. Whether you're assembling electronics, furniture, machinery, or structural components, these countersunk washers ensure a secure, polished result every time.

Made in Mainland China.

Key Features

• Material: Premium 304 stainless steel — rust-resistant and highly durable
• Sizes Available: M3, M4, M5, M6 (select your size from the dropdown menu)
• Size Reference: M3 x 11 x 2.5mm = 3mm (inner diameter) × 11mm (outer diameter) × 2.5mm (thickness)
• Profile: Bowl-type conical / concave-convex hollow fisheye design for flush, low-profile seating
• Function: Distributes clamping load evenly, reducing stress on fastened surfaces
• Packaging: Secure plastic packaging to keep washers organized and protected
• Versatile: Suitable for electrical, mechanical, woodworking, and general DIY assemblies

Size Guide

Note: Dimensions shown are for reference. Please verify specifications with the actual product. Select your preferred size and quantity from the dropdown menu above.

Common Applications

• Electronics and electrical panel assembly
• Furniture and cabinetry fastening
• Automotive and mechanical assemblies
• Woodworking and construction projects
• General DIY hardware and home improvement

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Frequently Asked Questions

Q: What material are these conical countersunk washers made from?

A: These washers are made from 304 stainless steel, a high-grade alloy known for its excellent corrosion resistance, durability, and strength — making them ideal for both indoor and outdoor applications.

Q: What does the bowl-type conical (fisheye) design do?

A: The concave-convex hollow fisheye profile allows the washer to sit flush against countersunk screw heads, distributing the clamping load evenly across the surface. This reduces surface damage and provides a clean, professional finish in your assemblies.

Q: Which sizes are available and how do I choose the right one?

A: These countersunk washers are available in M3, M4, M5, and M6 metric sizes. Select the size that matches your bolt or screw diameter from the dropdown menu. For reference, M3 = 3mm inner diameter, M4 = 4mm, M5 = 5mm, and M6 = 6mm. Always verify dimensions with your actual hardware before purchasing.

Q: Can I use these washers for outdoor or high-moisture environments?

A: Yes! The 304 stainless steel construction makes these washers highly resistant to rust and corrosion, so they perform reliably in outdoor, damp, or humid conditions.

Production & Packaging Notice

To maintain high stock availability and fast shipping times, our items are sourced from multiple verified manufacturing facilities. While the core quality, materials, and product specifications remain identical, you may notice slight variations in the packaging design, manufacturing origin, or the wording of the printed instructions.