Does this item come with the fuse terminal included? If so, how do I specify the amperage

I just ordered three of these - they each came with a 300A fuse. I was not expecting fuses to be included, so I had ordered them separately. If this is not a shipping/packaging mistake, it would be nice if the seller gave the option to choose a fuse size. While I can use a 300A on one of the terminals, I needed smaller ones for the others. I didn't buy them weeks ago because of the relatively high price of these fuses (typically ~$15 each). They were on sale for $10, so I got them now.

I have a new 100ah 12v lifepo battery. what fuse size do i need to go with this?

At solavanbuild, I use 150 amp fuses with 1/0 AWG battery cables in most of my installs.

I'm thinking of running a charge/power wire of the alternator to a trailer battery. Would it be OK to use this off the charge lead on the alternator?

I would recommend an automatic Charing Relay ACR. Blue sea makes great ones. I use their Mini-ACR because my boat alternator is less than 65A. Their standard handles up to 300A. Remember regardless, you will need TWO of these fuses, one at each battery. If your alternator puts out 60A then 75A fuses, if it puts out 100A than 130-150A fuses.

Can I use this as a bus bar (without a fuse), just to extend a 5/16 battery terminal. Thank you

No you can't.. The stud is insulated from the block.. And don't grind it down. As they are meant for fuses to complete the circuit. Just buy a battery post if you need that...

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5191

Product ID: 3836489

Details

Brand
Blue Sea
Color
Single Fuse
Connector Type
Screw
Current Rating
300 A
Gauge
1
Item Pitch
8 millimeters

⚡300A max current

🌊Weatherproof for harsh environments

🔩5/16" stud terminal size

NZ$181

Duties & taxes included

In stock

Sold byAmazon Cook IslandsDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

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Description

⚡ Fuse your circuits with confidence — power meets protection!

IGNITION PROTECTED - Compatible with MRBF fuses to ensure safe operation even near ignition sources
POWERHOUSE PROTECTION - Handles up to 300 amps for your high-demand circuits
SAFE SECURE CONNECTIONS - 5/16" stud terminal with insulating cap to prevent accidental shorts
UNIVERSAL FIT EASY MOUNT - Mounts on standard 3/8" battery posts for seamless integration
BUILT TO BRAVE THE ELEMENTS - Weatherproof design perfect for open-cockpit boats and tough conditions

The Blue Sea Systems 5191 Fuse Block Terminal supports 30-300A MRBF fuses, delivering robust, weatherproof circuit protection for marine and harsh environment applications. Featuring a 5/16" stud terminal and ignition protection, it mounts easily on 3/8" battery posts, ensuring safe, reliable power management for your critical DC systems.

Specifications

ASIN	B0019ZBTV4
Best Sellers Rank	#11,196 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #2 in Fuse Blocks (Tools & Home Improvement)
Brand Name	Blue Sea Systems
Color	Single Fuse
Connector Type	Screw
Current Rating	300 A
Customer Reviews	4.7 4.7 out of 5 stars (993)
Gauge	1
Global Trade Identification Number	00632085051914
Included Components	Blue Sea Systems 5191-BSS MRBF Terminal Fuse Block - 30A-300A
Item Dimensions W x H	2.5"W x 2"H
Item Type Name	Blue Sea Systems 5191-BSS MRBF Terminal Fuse Block - 30A-300A
Item Weight	2.56 ounces
Manufacturer	Blue Sea Systems
Material Type	Plastic
Model	5191-BSS
Mounting Type	hole mount
Number Of Contacts	10
Number Of Poles	1
Number of Items	1
Number of Positions	1
Part Number	5191-BSS
Pitch	8 millimeters
Specification Met	Sea
UPC	632085051914
Unit Count	1 Count
Voltage	58 volts

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NZ$181

Duties & taxes included

In stock

Sold byAmazon Cook IslandsDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Cook Islands.

Secure transaction

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TrustScore 4.5 | 7,300+ reviews

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