Fastronix Solutions 250A MEGA/AMG Inline Fuse Holder Kit — Sealed 4-Hole Mount, 5/16" Studs

The Fastronix 250 Amp MEGA/AMG Fuse Holder Kit is a heavy-duty inline fuse assembly that secures high-current circuits with a sealed holder, a 250A fuse, cable boots, and a four-hole mounting flange.

This kit is designed for high-current automotive, towing, and marine applications where protecting wiring and components from catastrophic shorts is critical. The assembly accepts MEGA/AMG-style 250 amp fuses and includes protective boots and mounting holes to keep the connection secure and insulated. It’s compact enough to fit in engine bays or electrical compartments while offering robust studs for large-gauge cables.

How does this fuse holder protect high-current wiring?

The Fastronix 250 Amp holder positions a 250A MEGA/AMG fuse inline with the power feed so an overcurrent or short will open the circuit at the fuse, isolating the fault. Its insulated boots and mounting flange reduce movement and exposure to conductive surfaces.

• Holds a 250 amp MEGA/AMG fuse to interrupt excessive current.
• Insulating cable boots prevent accidental shorts to chassis or ground.
• Mounting holes secure the holder to a stable surface to limit vibration.

What cable sizes and terminations fit the studs?

The kit uses 5/16" studs sized to accept large ring terminals and wire up to 2/0 gauge, making it suitable for high-amp battery and alternator feeds. Boots are included to cover the studs and maintain a neat, protected connection.

• 5/16" studs accept common battery ring terminals.
• Compatible with wire up to 2/0 gauge for heavy loads.
• Included boots fit over studs to keep moisture and debris out.

Can I mount this holder in a vehicle being towed or in other exposed locations?

Yes — the four mounting holes let you bolt the holder to a chassis panel, bulkhead, or a dedicated electrical board so it won’t shift during towing or off-road use. Proper mounting helps prevent shorts caused by loose hardware contacting other metal parts.

• Four convenient mounting holes keep the holder secure under vibration.
• Low-profile flange fits tight engine-bay spaces and tow brackets.
• Booted studs and sealed holder reduce risk of corrosion in exposed areas.

What’s included and are replacement fuses available?

The kit ships with the fuse holder, a 250 amp MEGA/AMG fuse installed, and cable boot covers for both studs. For replacements, Fastronix lists the compatible spare as model 501-149, sold separately.

• One fuse holder preloaded with a 250A MEGA/AMG fuse.
• Cable boot covers to insulate both studs and reduce corrosion risk.
• Reference spare fuse part: Fastronix 501-149 (sold separately).

Who is this for? Installers, mechanics, and vehicle owners who need a compact, serviceable overcurrent protection point for high-current systems will benefit from this kit. It’s targeted at automotive towing setups, marine battery banks, off-road rigs, and fleet vehicles where a reliable, easily replaceable 250 amp fuse and a secure mounting option are required. If you need a robust inline fuse solution for 2/0 gauge wiring and large ring terminals, this kit delivers the hardware and protection to keep heavy-current circuits controlled and serviceable.