Serlainxin 50ft 4-pin 5-wire Trailer Wire Harness – Extended Length Boat Trailer Wiring Kit for RV & Marine

Overview

Meet the Serlainxin 50-foot trailer wiring harness, a premium towing wiring solution designed for reliability on the road and at the marina. With a 4‑pin flat plug and a 5‑wire setup, it keeps tail, brake, turn, and ground circuits organized across longer trailers. The extended length accommodates diverse trailer configurations, from fishing boats to RVs, without forcing compromises on connections or alignment.

Designed for real-world use, this kit combines practical materials with thoughtful routing. The brown, green, yellow, and white conductors are easy to map to each function, helping you identify connections at a glance during setup or maintenance.

Durability and reliability

Durable materials and weather-ready construction are at the core of this harness. The wires feature a thickened PVC insulation and copper conductors, engineered to resist aging from sun, salt spray, and moisture exposure. The rugged build helps maintain conductivity and performance across seasons and environments.

Two bulleted highlights

• Long, flexible run: 50 ft total length with 42 ft of male wire and 8 ft of female wire for extended trailer installations.
• Clear color coding: Four color‑coded wires (brown, green, yellow, white) to simplify identification and troubleshooting.

Installation and compatibility

The wishbone wire design splits at the trailer tongue, running neatly down each side of the frame. This thoughtful routing minimizes splicing and keeps wiring tidy, which can make installation smoother and maintenance easier over time. The standard 4-pin flat plug ensures broad compatibility with a wide range of trailer and vehicle setups.

• Universal 4-pin flat plug for broad compatibility with boat, utility, and RV trailers.
• 18-gauge copper conductors provide reliable performance for everyday towing needs.

Real-world uses

Ideal for extending trailer electrical runs, upgrading older wiring, or replacing worn wiring on long boats or utility trailers. The combination of length, color coding, and a practical installation design makes it a versatile choice for DIYers and professionals alike.