--- product_id: 3836489 title: "Blue Sea Systems MRBF Terminal Fuse Block, 30-300A" brand: "blue sea systems" price: "AR$112858" currency: ARS in_stock: true category: "Blue Sea Systems" url: https://www.desertcart.com.ar/products/3836489-blue-sea-systems-mrbf-terminal-fuse-block-30-300a store_origin: AR region: Argentina --- # 300A max current Weatherproof for harsh environments 5/16" stud terminal size Blue Sea Systems MRBF Terminal Fuse Block, 30-300A **Brand:** blue sea systems **Price:** AR$112858 **Availability:** ✅ In Stock ## Summary > ⚡ Fuse your circuits with confidence — power meets protection! ## Quick Answers - **What is this?** Blue Sea Systems MRBF Terminal Fuse Block, 30-300A by blue sea systems - **How much does it cost?** AR$112858 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.com.ar](https://www.desertcart.com.ar/products/3836489-blue-sea-systems-mrbf-terminal-fuse-block-30-300a) ## Best For - blue sea systems enthusiasts ## Why This Product - Trusted blue sea systems brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **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 ## Overview 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. ## Description Fuse Block, Battery Post Mount, 1 stud, MFG# 5191, Accepts MRBF fuses from 30-300 Amp. Mounts on 3/8" (MN10) Battery Post, single 5/16" stud for wire connections. Fuse not included. ## Features - Voltage Max Operating: 58V DC, Amps Max Operating: 300A per block, Terminal Fuses Avail.: 30A-300A, Terminal Stud Size: 5/16"-18 (8mm), Mounting Hole Size: 10 (5mm)3/8" - Compact, high-amp fuse—appropriate for DC Main, inverter, windlass, and bow thruster circuit protection - Weatherproof – suitable for small open-cockpit boats and other harsh environments - Insulating cap prevents accidental shorts - Ignition protected when used with MRBF fuses - Fuses sold separately - Fit type: Universal Fit ## Technical Specifications | Specification | Value | |---------------|-------| | 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 | ## Product Details - **Brand:** Blue Sea Systems - **Color:** Single Fuse - **Connector Type:** Screw - **Current Rating:** 300 A - **Gauge:** 1 - **Item Pitch:** 8 millimeters - **Material:** Plastic - **Mounting Type:** hole mount - **Number Of Contacts:** 10 - **Voltage:** 58 volts ## Images ![Blue Sea Systems MRBF Terminal Fuse Block, 30-300A - Image 1](https://m.media-amazon.com/images/I/61vPpZ-72JL.jpg) ## Available Options This product comes in different **Color, Style** options. ## Questions & Answers **Q: Does this item come with the fuse terminal included? If so, how do I specify the amperage** A: 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. **Q: I have a new 100ah 12v lifepo battery. what fuse size do i need to go with this?** A: At solavanbuild, I use 150 amp fuses with 1/0 AWG battery cables in most of my installs. **Q: 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?** A: 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. **Q: Can I use this as a bus bar (without a fuse), just to extend a 5/16 battery terminal. Thank you** A: 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... --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.com.ar/products/3836489-blue-sea-systems-mrbf-terminal-fuse-block-30-300a](https://www.desertcart.com.ar/products/3836489-blue-sea-systems-mrbf-terminal-fuse-block-30-300a) --- *Product available on Desertcart Argentina* *Store origin: AR* *Last updated: 2026-09-16*