Trailer Connectors
Attwood Marine 7663-5 4-Way Flat Trailer Wiring Harness Kit 18" Plug / 48" Socket
What Are Trailer Connectors and Why Do They Matter?
Trailer connectors are the electrical lifeline between your tow vehicle and whatever you're hauling — whether that's a boat on its way to the lake, an RV heading down the highway, or a utility trailer loaded with gear. These small but critical components transmit the signals that control your trailer's brake lights, turn signals, running lights, electric brakes, and auxiliary power. Without a reliable, weatherproof connection, you risk non-functional trailer lighting — a serious safety hazard for you and every other driver on the road.
Understanding which connector type you need is the first step to making the right purchase. The most common styles include:
- 4-Way Flat — The standard for light-duty trailers, connecting tail lights, brake lights, and turn signals in a simple, flat-pin format.
- 5-Way Flat — Adds a dedicated auxiliary circuit, common on trailers with additional electrical needs.
- 6-Way Round — A popular choice for boat trailers and agricultural equipment, offering more circuits in a round configuration.
- 7-Way RV Blade — The go-to for larger trailers and RVs, supporting electric brakes, a backup circuit, and auxiliary power in addition to all standard lighting functions.
When shopping for a trailer connector, consider the connector type required by both your tow vehicle and your trailer, the quality of the housing materials (corrosion resistance is especially important for marine environments), and whether you need a vehicle-side or trailer-side connector — or both.
Top Trailer Connector Brands
Hopkins is widely recognized as a leader in towing electrical products. Their Endurance™ line of connectors and wiring kits is designed for maximum durability and enhanced weatherproofing, backed by a 3-year performance guarantee. Hopkins also pioneered the patented Multi-Tow™ design, which allows a single connector to interface with multiple trailer types — an ideal solution for those who tow different rigs throughout the season.
Draw-Tite has been a trusted name in towing accessories since 1946, building a reputation for precision-fit electrical solutions that complement their hitch systems. Their T-One® T-Connector harnesses are engineered to integrate seamlessly with a vehicle's factory wiring, and many feature circuit-protected ModuLite® HD modules to safeguard your tow vehicle's electrical system during hookup.
Pico Wiring is a go-to source for a broad range of trailer connector styles and configurations. Their connector kits are known for color-coded, polarized wiring that makes installation straightforward, and they offer solutions spanning from simple 2-way molded connectors all the way up to complete multi-conductor trailer wiring kits with brackets and splice connectors included.
Choosing the Right Trailer Connector
Always match your connector to the number of circuits your trailer actually uses — don't downgrade to a 4-flat if your trailer has electric brakes requiring a 7-way. For marine and RV applications, prioritize connectors with non-corrosive thermoplastic housings and internal sealing to keep moisture out. If your tow vehicle has a factory tow package, look for OEM-style connectors that plug directly into the existing socket without cutting or splicing for the cleanest, most weatherproof fit possible.