Flat Washer, M4, 0.8 mm Thick, OD 9 mm
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You have 30 days to request a return. All sale items are final sale.
A corrosion-resistant flat washer made for M4 hardware, sized to help spread load and improve clamping performance.
Key Features
- Designed as a flat washer for M4 threaded applications
- Material: 18-8 stainless steel
- Size: 0.8 mm thick with 9 mm outside diameter (OD)
Intended Use
- M4 marine and industrial fastener installations
- General-purpose fastening where a flat washer is needed for load distribution
Product Details
- Brand / line: SeaChoice (LNS)
- Part number / SKU: 50-01231
- Washer type: Flat Washer
- Thread size: M4
- Thickness: 0.8 mm
- Outside diameter (OD): 9 mm
- Material: 18-8 stainless steel
Parts Desk Insights
Best Use Case: Use this flat washer with M4 screws/bolts to help distribute clamping force and reduce the chance of pull-through on softer or thinner mounting surfaces.
Common Issues: If the washer thickness or OD doesn’t match the hardware or clearance requirements, you may run into insufficient seating or fitment interference. Also verify that the mating fastener head and mounting surface are compatible with stainless washer use in your environment.
Related Products & Accessories
- Flat Washer, M4 (related sizes) - Browse the Fasteners & Mounting category for additional flat washer sizes and thicknesses.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 1-3 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.