CURT Custom Wiring provides everything you need to connect your vehicle's electrical system to a trailer. With plug-and-play connectors, a custom wiring harness easily integrates with your vehicle taillights to provide a standard trailer wiring connector, typically in the form of a 4-way flat. This custom wiring harness features a vehicle-specific design to perfectly fit certain years of the Toyota Sienna. It uses OEM-compatible connectors to "T" into the vehicle's taillight assembly and provides a standard 4-way flat output to power the taillights, brake lights, and turn signals on your trailer. This custom wiring harness comes with a rubber dust cover. This cover keeps the connection points clean and well protected when the connector is not in use.• Plugs into vehicle taillight assembly to provide a 4-way flat socket• Simple plug-and-play design eliminates the need for cutting or splicing• 4-way flat output connects taillights, brake lights, and turn signals• Equipped with taillight converter for vehicle-trailer compatibility• Constructed with SMT circuitry for better performance and durability• Dust cover included to keep connector clean when not in useCompatible Vehicles2021-2024 Toyota Sienna Provides a standard 4-way flat output to power taillights, brake lights, & turn signals Dust cover included to keep connector clean when not in use | Curt 56489 Custom Wiring Harness, 4-Way Flat, Select Toyota Sienna