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Over 50 years of Trusted Marine Service

Sierra FS84170 Marine Rated Battery Fuse, 100A, Yellow

Original price $27.99 - Original price $27.99
Original price
$27.99
$27.99 - $27.99
Current price $27.99
Item locally warehoused

Free returns on all eligible orders

You have 30 days to request a return. All sale items are final sale.

Sierra FS84170 is a 100A, yellow marine rated battery fuse designed to mount directly on the positive battery stud to provide DC circuit protection at the power source. Built for demanding, high-vibration marine installations, it features an insulating protective cap and a clear visual indicator for easy fault checks.

Key Features

  • Ignition protected when used with Sierra MRBF Fuses
  • Mounts directly to the positive battery stud for source-side circuit protection
  • Bolt-down design for high-vibration applications
  • Standard isolated M8 stud design supports terminal stacking
  • Protective insulating cap helps prevent accidental shorts
  • Compact design for high-current protection in tight spaces
  • Designed for DC main, bow thruster, inverter, and windlass circuit protection
  • 100A (yellow) fuse rating with 300A maximum amperage
  • Meets ABYC requirements for DC main circuit protection on large battery banks with high-interrupt rating
  • Easy fault indication with clear fuse display
  • Color-coded amperage identifier

Intended Use

  • Marine DC battery banks
  • DC main battery circuit protection
  • Bow thruster circuit protection
  • Inverter circuit protection
  • Windlass circuit protection
  • High-vibration marine electrical installations

Product Details

  • Sierra marine rated battery fuse (MRBF)
  • Part number/SKU: FS84170 (SKU shown: 11-FS84170)
  • Amperage rating: 100A
  • Color: Yellow
  • Mounting style: Bolt-down on positive battery stud
  • Stud design: Isolated M8 for terminal stacking
  • Maximum amperage: 300A
  • ABYC: Meets requirements for DC main circuit protection on large battery banks with high-interrupt rating
  • Fault indication: Clear fuse display

Parts Desk Insights

Best Use Case: Use this MRBF battery fuse at the battery’s positive stud when you need compact, source-side DC main circuit protection for systems like inverters, bow thrusters, and windlasses—especially when space is tight and vibration is present.

Common Issues: If troubleshooting a blown condition, verify the fuse rating matches the circuit and that the mounting surfaces and connections are clean and secure. Also check the insulating/protective cap and confirm proper terminal stacking on the isolated M8 stud to avoid unintended shorts.

Related Products & Accessories

Browse related Breakers, Fuses & Fuse Holders 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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