Automotive Parts 300A Waterproof Circuit Breaker (12V-48V DC) - 3 Pack
Set of three 300A waterproof circuit breakers with copper ring terminals, washers, and mounting screws.
Diagram showing 300A waterproof circuit breaker operation with push button reset and kill switch functionality.
Dimensional diagram of a 300Amp waterproof circuit breaker showing product measurements and 1/4-28 stud size.
300A waterproof circuit breaker with manual reset button and mounting holes, showing product features and specifications.
Collage showing wide application of 300Amp circuit breakers for vehicles and shipping containers.
Single 300Amp waterproof circuit breaker with battery pole connection diagram and installation hardware.
Group of friends sitting on the tailgate of a pickup truck by a lake, representing reliable 300Amp circuit breaker use.
Set of three 300A waterproof circuit breakers with copper ring terminals, washers, and mounting screws.
Diagram showing 300A waterproof circuit breaker operation with push button reset and kill switch functionality.
Dimensional diagram of a 300Amp waterproof circuit breaker showing product measurements and 1/4-28 stud size.
300A waterproof circuit breaker with manual reset button and mounting holes, showing product features and specifications.
Collage showing wide application of 300Amp circuit breakers for vehicles and shipping containers.
Single 300Amp waterproof circuit breaker with battery pole connection diagram and installation hardware.
Group of friends sitting on the tailgate of a pickup truck by a lake, representing reliable 300Amp circuit breaker use.
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300A Waterproof Circuit Breaker (12V-48V DC) - 3 Pack

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300A Waterproof Circuit Breaker (12V-48V DC)

Key Features

  • 300 amp rated manual-reset circuit breaker for 12V-48V DC systems
  • Push-button reset lever also functions as a manual disconnect switch
  • Waterproof housing suited to marine, engine compartment, and bilge environments
  • Surface-mount design with threaded stud terminals for heavy-gauge wiring

Replaces / Cross-Reference Part Numbers

This is a generic, unbranded circuit breaker sold under multiple private-label names with no manufacturer part number. It does not cross-reference to a specific OEM part; compatibility should be confirmed by amperage rating (300A), voltage range (12V-48V DC), and stud/terminal size against the existing breaker or wiring being replaced.

Compatibility & Fitment

  • Operating voltage: 12V-48V DC
  • Rated current: 300A
  • Suitable for boats, yachts, RVs, trailers, trolling motors, winches, and heavy-duty DC electrical circuits
  • Stud size varies by supplier at this amperage (commonly 1/4" or 3/8"); confirm stud size and wire gauge compatibility before ordering

When to Replace

  • Breaker fails to reset or hold a closed circuit after repeated attempts
  • Housing shows cracking, corrosion, or water intrusion at the terminals
  • Breaker trips well below its rated 300A load under normal operating conditions
  • Terminals show heat discoloration, pitting, or looseness that can't be corrected by tightening

Installation Tips

  • Disconnect the battery or power source before installing or replacing any circuit breaker
  • Confirm the breaker's amperage rating matches the circuit's wiring gauge and load requirements
  • Mount on a flat, stable surface away from direct exposure to fuel, oil, or excessive vibration
  • Torque terminal connections to the wire lug manufacturer's specification to prevent loosening over time
  • If unfamiliar with high-amperage DC wiring, have the installation checked by a qualified marine or auto electrician
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  • Manual Reset Switch

    Manual Reset Switch

    Simple manual control with reset arm, serving as both a switch for battery/DC sound amplifier system
  • Superior Quality

    Superior Quality

    Premium steel studs are stainless with protective stud insulators included.
  • Waterproof Level IP67

    Waterproof Level IP67

    This product adopts I P67 waterproof thermal-plastic mount cover ensuring long life service.
  • Package Include

    Package Include

    3 x 300Amp Circuit Breaker | 6 x 6AWG-1/4'' Wire Lugs | 12 x M6 Copper Washers | 6 x Self Tapping Screws
BRINGING RELIABILITY TO THE SWITCH

BRINGING RELIABILITY TO THE SWITCH

Model
300 Amp Circuit Breaker
Voltage Rating
12-48V DC
Interrupt Capacity
3KA@48VDC
Operating Temperature
-32°C to 82°C
Storage Temperature
-34°C to 149°C
Terminal Size
1/4"-28

FAQ

These breakers are designed for high-amperage DC electrical systems, commonly used in marine trolling motors, automotive audio systems, RVs, solar power setups, and battery charging systems. They provide essential overcurrent protection for heavy-duty circuits.
These are manual reset breakers. If the circuit is overloaded, the internal mechanism will trip and the manual reset lever will flip to the 'off' position. You can visually inspect the lever to confirm if it has tripped.
Once the fault in your electrical system has been identified and corrected, simply push the manual reset lever back into the 'on' position. There is no need to replace a fuse; the breaker is designed to be reusable.
Yes, these breakers are compatible with a wide range of DC voltages, typically handling up to 48V DC. They are suitable for standard 12V, 24V, and 36V battery systems.
Ensure that your wire gauge is properly sized for a 300-amp load. Using wire that is too thin for this amperage can lead to excessive heat and voltage drop. Additionally, always mount the breaker in a dry, accessible location to ensure the manual reset lever can be reached easily.
While the manual reset lever can be used to disconnect the circuit for maintenance, it is primarily designed as a protective device. It is not intended to be used as a frequent power switch for daily operation.