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Celebrating over 50 years of Trusted Marine Service
Over 50 years of Trusted Marine Service

Seachoice 18-8 Stainless Steel Acorn Cap Nuts, 3/8-16 Size, Pack of 50

Original price $100.69 - Original price $100.69
Original price
$100.69
$100.69 - $100.69
Current price $100.69
Item locally warehoused

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 give you a finished, rounded look while helping protect bolt threads—ideal when only a small amount of bolt is exposed.

Key Features

  • Closed nut design with smooth, rounded head for an attractive finish
  • Helps protect the thread when very little bolt is exposed
  • Smooth rounded head covers and shields the threads
  • 18-8 stainless steel for superior corrosion resistance
  • Manufacturer part number: 50-00591
  • Pack quantity: 50

Intended Use

  • Marine and boating hardware projects
  • Fastening and mounting applications where a finished cap-nut look is desired
  • General replacement fastener needs requiring 3/8-16 (coarse) threads and acorn (cap) nut style

Product Details

  • 3/8-16 size acorn cap nuts
  • Material: 18-8 stainless steel
  • Closed nut with smooth rounded head (acorn/cap nut style)
  • Manufacturer part number: 50-00591
  • Pack of 50

Parts Desk Insights

Best Use Case: Use these cap nuts on marine/boating installations where you want the bolt end to look clean and protected—especially in spots where only a short length of thread is above the joint.

Common Issues: Thread mismatch is the most common issue—double-check you’re using a 3/8-16 (coarse) bolt. Also confirm the joint stack height so the capped head sits as intended and fully covers the exposed threads.

Related Products & Accessories

Browse related Bulk Fasteners to complete the installation.

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.

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