Blue Sea 30-300A Marine Rated Battery (MRBF) Single Terminal Fuse

Space-Saving High-Amperage Circuit Protection

*Please note Blue Sea fuses are manufactured by Eaton, Bussman or Ionnic and may have labelling of one of these manufacturers on the product and/or packaging.

The Blue Sea Marine Rated Battery (MRBF) Single Terminal Fuse Block solves one of the most common challenges in marine and automotive electrical installations: limited space. By mounting directly onto the battery terminal, this fuse block eliminates the need for short, difficult-to-install cable runs between the battery and a traditional firewall-mounted fuse holder. This design not only saves valuable room in crowded battery compartments but also reduces resistance and potential failure points in your high-current cabling.

Engineered for demanding environments, this unit is ideal for protecting high-load circuits such as inverters, windlasses, and bow thrusters. With a maximum voltage rating of 58V DC, it is perfectly suited for modern 12V, 24V, and 48V electrical systems found in boats, caravans, and off-grid 4WD setups.

Direct Battery Terminal Mounting

The primary advantage of the Blue Sea Marine Rated Battery (MRBF) Single Terminal Fuse Block is its ability to interface directly with the power source. It is designed to mount securely onto a standard 3/8" (Approx. M10) battery terminal stud. By fusing the circuit right at the battery post, you ensure maximum safety; if a fault occurs in the main cable running to your equipment, the fuse will blow immediately at the source, preventing potential fire hazards associated with unprotected live cables.

Versatile and Robust Design

Constructed with marine-grade materials, this fuse block is built to withstand the harsh conditions of the Australian outdoors. The hardware includes stainless steel studs and tin-plated copper bus bars for maximum conductivity and corrosion resistance. The unit features M8 (Approx. 8mm) studs for connecting your load cables, accommodating heavy-duty lugs and cabling required for loads up to 300A.

Safety is paramount in high-current applications. The included insulating cap prevents accidental shorts across the conductive terminals, satisfying ABYC/USCG requirements for insulation when installed correctly. The versatile design allows for flexible cable orientation, making it easier to route heavy gauge wire in tight lockers.

Single Circuit Simplicity

This model features a compact single-terminal design, perfect for dedicating a fused line to a specific high-load device or a main DC distribution panel where footprint minimization is critical.

Key Features

• High Interrupt Rating: Safely handles high amperage loads up to 300A.
• Compact Footprint: Mounts directly to 3/8" (Approx. M10) battery studs, saving panel space.
• Voltage Versatility: Rated for 58V DC, suitable for 12V, 24V, and 48V systems.
• Secure Connections: Uses M8 (Approx. 8mm) output studs for secure cable termination.
• Safety Cap: Insulating cap protects against accidental short circuits.
• Corrosion Resistant: Tinned copper and marine-grade stainless steel hardware.

Whether you are refitting a yacht or building a custom tourer, the Blue Sea Marine Rated Battery (MRBF) Single Terminal Fuse Block provides professional, reliable, and neat circuit protection exactly where you need it.

Secure your high-current electrical system today with this compact terminal fuse solution.