Ancor 321503 Marine Grade™ Heat Shrink Ring Terminals, 5/16" Fastener, 8 Wire, Red, 3/Pk
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You have 30 days to request a return. All sale items are final sale.
Ancor 321503 Marine Grade™ adhesive-lined heat shrink ring terminals are designed to create a sealed, vibration-resistant connection in demanding marine electrical systems. Tinned copper helps resist corrosion, while the heat shrink sleeve forms a tight seal for strain relief.
Key Features
- Tinned copper construction helps resist corrosion for reliable current flow in marine environments.
- Adhesive-lined heat shrink tubing shrinks to form a tight seal around the connection.
- Built for vibration and strain relief to help protect electrical terminations.
Intended Use
- Marine electrical wiring and battery connections
- DC wiring and power connections where moisture sealing and strain relief are important
- Replacement or upgrade of ring terminal connections in boats and marine equipment
Product Details
- Brand: Ancor
- Model/Part: 321503 (SKU: 639-321503)
- Type: Marine Grade™ heat shrink ring terminals (adhesive lined)
- Wire size: 8 AWG
- Fastener/stud size: 5/16"
- Color: Red
- Quantity: 3 terminals per pack
- Terminal feature: tinned copper for corrosion resistance
Parts Desk Insights
Best Use Case: Great for sealing ring-terminal connections on marine wiring where you want both a secure mechanical termination and a heat-activated protective sleeve.
Common Issues: Avoid overheating the sleeve during installation—apply heat evenly until the adhesive fully activates and the tubing shrinks snugly. Also, confirm the stud/fastener size matches 5/16" before crimping to prevent loose fit or poor electrical contact.
Related Products & Accessories
- Browse Heat Shrink & Adhesive Lined terminals - See additional adhesive-lined heat shrink terminal options for your wiring needs.
- Browse Wiring & Connections - Pair these terminals with compatible wiring supplies and connection hardware.
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.