Everything You Need to Know About Boat Trailer Plug Types

Staying afloat and water-bound with your boat calls for a reliable trailer plug. Without the right kind of trailer plug connection, you won't be able to tow your boat wherever it needs to go. But choosing the right type of trailer plug for your boat can seem intimidating, especially if you're new to boating. Knowing the different types of boat trailer plugs is the first step to securing a safe, reliable connection for you and your boat.

When you pull up to the boat launch or prepare for a day out on the lake, a correctly installed boat trailer plug is essential to secure a reliable connection for your boat. Whether you're a novice or an experienced boat trailer driver, it's important to understand the different types of trailer plugs so you can ensure your boat and trailer are properly connected. Here we will cover the available trailer plug options and the advantages they offer.

7 Pin Round Trailer Plugs

The 7 round pin trailer plugs are commonly used to pull large boats, although other lighter duty trailers may use them as well. This type of plug is easy to install, since it only has 7 pins to connect, and provides more flexibility than other types of trailer plugs. With this type of plug, seven different circuits are utilized, which allows for more power options while towing. The 7 round pin design allows you to use the same plug to control various auxiliary functions such as running lights, navigation lights, electric brakes, a reverse light, and battery charging.

4 Flat Trailer Plugs

The 4 flat trailer plugs are most common for smaller trailers that don’t have several electric components. With just four circuits, this type of plug allows for plenty of flexibility to meet the needs of things like running lights and signal lights. Although some larger boats still use the 4 flat trailer plugs, they are generally found on trailers that are under 25 feet in length. This type of trailer plug has four electrical circuits, with two of them acting as the ground connection and two functioning as the signal connection.

5 Flat Trailer Plugs

The 5 flat trailer plugs are similar to the 4 flat plugs in that they are mainly used for smaller trailers. This type of plug is typically used for trailers that have electric brakes, and the five electrical circuits provide enough wiring for the brakes and other electrical components such as running lights and signal lights. This trailer plug has five flat pins, with the ground connection split into two of the pins.

7 Round Pin Plug with 4 Flat Trailer Plugs

The 7 round pin plug with 4 flat trailer plugs is typically used in tandem with a vehicle that has both a 7 round pin and a 4 flat plug. This type of combination plug is especially useful because it allows you to plug in both plugs at the same time. This plug can be used with a variety of trailers, including small boats, and provides seven circuits for controlling various auxiliary functions while towing, including running lights and brakes.

Conclusion

Knowing the various types of boat trailer plugs and the benefits they offer can help you make the right choice when selecting the type of plug for your boat trailer. Whether you choose a 7 round pin plug, a 4 flat plug, or a 5 flat plug, having the correct plug on hand and correctly installed is essential for a safe and reliable connection for your boat trailer.

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