Stop splicing wires and wrestling with bare connectors. The CURT 55441 T-One T-connector plugs directly into your vehicle's factory tail light harness socket, instantly giving you a standard 4-flat trailer output for brake lights, turn signals, and running lights -- no wire cutting, no electrical tape, no guesswork.
The CURT 55441 is part of CURT's T-One connector family -- vehicle-specific plug-in harnesses engineered to match the factory tail light socket of a particular make and model. Rather than splicing into your truck or SUV's wiring, you unplug the factory socket, plug in the T-connector, and restore the factory socket. The harness then adds a 4-flat trailer output at the rear bumper area, ready for your trailer's connector.
This is the correct solution for towing a utility trailer, boat trailer, travel trailer, or pop-up camper when your vehicle lacks a factory trailer wiring outlet. Because the connector is vehicle-specific, it maintains proper load handling and does not overload your tail light circuit.
Plugs directly into the factory tail light socket -- no wire cutting, no soldering, and no risk of voiding electrical warranties.
Standard 4-way flat connector covers left turn/brake, right turn/brake, running lights, and ground -- all that most trailers and campers require.
Engineered to match a specific vehicle's factory harness plug, ensuring proper signal routing and a secure, rattle-free connection.
Connector housing and contacts are built to withstand road spray, moisture, and temperature swings common to towing applications.
CURT's T-One series uses a "T" arrangement: the harness intercepts the signal from your vehicle's tail light module, passes it through unchanged to your factory tail light, and simultaneously sends the same signal out through the 4-flat trailer connector. The result is that your vehicle lights work exactly as before -- and your trailer gets clean, properly switched signals without any relay module required (on most compatible vehicles).
The 55441 is the plug-in harness portion of this system. It does not include a converter module, brake controller, or 7-way adapter. If your trailer runs only 4-flat wiring (running lights, turn signals, brake lights), this harness is a complete solution. Trailers requiring a 7-pin connection need a separate 4-to-7 adapter.
Installation is typically a 15-30 minute job with no special tools beyond a trim panel removal tool in some applications. General process:
CURT organizes trailer wiring into several categories. T-One connectors like the 55441 are the entry-level plug-in solution for vehicles with compatible factory tail light sockets. For vehicles with LED tail lights that use a multiplex (CAN bus) system, CURT offers T-One connectors with integrated modulite or EcoHitch converter modules. The 55441 is designed for conventional (non-CAN-bus) tail light circuits.
If you need a 7-way RV blade output for a trailer with electric brakes or a 12V charge line, combine this T-One with a CURT 4-to-7 adapter (sold separately).