Seachoice 18-8 Stainless Steel Acorn Cap Nuts, 5/16-18 Size, Pack of 50
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
Seachoice 18-8 stainless steel acorn cap nuts provide a clean, closed finish over the threaded end of a bolt—ideal for projects where only a small amount of bolt is exposed.
Key Features
- Closed nut design with a smooth, rounded acorn head for an attractive finish
- Helps protect the thread when very little of the bolt is exposed
- 18-8 stainless steel for superior corrosion resistance
- Size: 5/16-18
- Pack quantity: 50
- Manufacturer part number: 50-00589
Intended Use
- General marine and boating fastening projects
- Replacement hardware for saltwater-exposed assemblies
- Projects where you want a finished, thread-protecting nut head
Product Details
- Type: Acorn cap nut (closed nut)
- Material: 18-8 stainless steel
- Thread size: 5/16-18
- Pack size: 50
- Manufacturer part number: 50-00589
- SKU/Variant: 50-00589
- Quantity: 50
Parts Desk Insights
Best Use Case: Use these acorn cap nuts when you want a finished dome top and added protection for the exposed thread end—especially in tight assemblies where only a short section of bolt is visible.
Common Issues: For best results, confirm thread size (5/16-18) before installation, and make sure the mating surfaces are clean so the nut seats evenly on the part being fastened.
Related Products & Accessories
- Browse Fasteners & Mounting - Explore matching nuts, bolts, and marine fastener accessories.
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.