Anderson-style plugs are commonly used in 4WD, caravan, camper trailer and off-grid electrical systems. They provide a practical way to connect and disconnect power for accessories such as solar panels, DC-DC chargers, fridges, inverters and general 12V or 24V equipment.
One of the most common questions is which plug size to use: SB50, SB120 or SB175. Each size suits a different type of setup, depending on current draw, cable size and how the connection will be used.
What is an SB50 Anderson Plug?
The SB50 is one of the most common Anderson-style plug sizes used in 4WD and caravan setups.
It is commonly used for:
- Solar input connections
- Fridge power connections
- General 12V accessories
- Battery box connections
- Low to medium current applications
- Trailer and canopy wiring
For many touring setups, the SB50 is the most practical choice. It is compact, easy to package and suitable for many common accessory circuits when correctly matched to the wiring, fuse and load.
What is an SB120 Anderson Plug?
The SB120 is larger than the SB50 and is generally used where a higher current connection is required.
It may suit applications such as:
- Larger DC power feeds
- Higher-output charging systems
- Larger auxiliary battery systems
- More demanding accessory circuits
- Custom 12V or 24V installations
Because it is physically larger, the SB120 requires more mounting space than an SB50. It is best suited to installations where the electrical load, cable size and fuse rating justify the larger connector.
What is an SB175 Anderson Plug?
The SB175 is larger again and is generally used for heavier-duty electrical connections.
It may suit applications such as:
- High-current power feeds
- Inverter connections
- Winch-related connections
- Large battery systems
- Heavy-duty 12V or 24V setups
The SB175 is not usually required for basic accessory wiring. It is better suited to systems where high current capacity and larger cable sizes are needed.
Quick Comparison
Anderson-style SB connectors are named after their nominal current rating. The exact capacity always depends on the contacts and cable fitted, but as a rough guide:
| Connector | Nominal current rating | Typical use |
|---|---|---|
| SB50 | ~50A nominal (the genuine housing is rated higher with the largest contacts) | Solar, fridge and general 12V/24V accessories |
| SB120 | ~120A nominal | Larger charging systems and power feeds |
| SB175 | ~175A nominal | Inverters, winch-related and heavy-duty feeds |
These figures are a starting point only. Always match the connector to the actual current draw, cable size and fuse rating for your circuit.
SB50
- Common in 4WD and caravan setups
- Compact size
- Useful for solar, fridge and accessory power
- Good for low to medium current applications
SB120
- Larger than SB50
- Suits higher-current connections
- Useful for larger charging or power systems
- Requires more mounting space
SB175
- Heavy-duty connector size
- Suits high-current setups
- Useful for large inverters, winch-related wiring or major power feeds
- Requires the most mounting space
Which Size Should You Choose?
For most general 4WD, caravan and canopy electrical setups, the SB50 is usually the most common starting point.
Choose SB50 if you are connecting:
- Solar input
- Fridge power
- General accessories
- Battery boxes
- Standard canopy wiring
Choose SB120 if you need:
- A larger power connection
- Higher current capacity
- Larger cable compatibility
- A more robust connection than SB50
Choose SB175 if you are building:
- A heavy-duty power system
- A large inverter connection
- A winch or high-current accessory setup
- A larger 12V or 24V electrical system
Important Installation Note
The connector size is only one part of the electrical system. The correct plug should always be matched with suitable cable size, fuse protection, current draw and installation method.
If you are unsure, speak with a qualified auto electrician before installing or modifying high-current electrical systems.
Mounting Anderson Plugs Cleanly
Once you have selected the right plug size, read our canopy mounting guide before marking or drilling the panel.
AFS Offroad Anderson Plug Surface Mount Kits are designed to provide a clean, professional mounting solution for SB50, SB120 and SB175 Anderson-style plugs. They are suitable for 4WD canopies, drawer systems, caravans, trailers, panels and custom 12V/24V setups.
Our surface mounts are Australian-made, 3D printed from durable ASA-GF and available in single, double and triple configurations.
Shop Anderson Plug Surface Mount Kits
Explore the AFS Offroad range of Anderson plug surface mount kits for 4WD, caravan and off-grid electrical setups.
Important safety information
Water protection: Dust covers, mounting gaskets and connector mounts discussed in this guide are not waterproof or watertight. Install them in a protected location away from direct spray, high-pressure water and immersion.
Electrical installation: All electrical wiring and installation must be carried out by a suitably qualified electrician or auto electrician, as appropriate. The installer must confirm cable sizing, terminations, fusing, circuit protection and suitability for the application.