4-pin flat trailer plug tester, insert the tester into the trailer, test the tail lights, brake lights, and turn signals, and check the faulty area based on the LED lights
4-way trailer tester is made of high-quality materials, which are wear-resistant, sturdy, and durable. It can be used for a long time to maintain safe and stable contact, and is easy to grip. The tail end has a mouth, which can be hung on your keychain, lightweight and convenient
Trailer harness tester plug is easy to use, and for each electrical function, the LED will light up, indicating a good signal. Insert the trailer tester into the vehicle socket, activate the LED signal to check them
Trailer testing adapter does not require tools to plug and play, and does not require anything else to effectively test the trailer wiring harness. It has a double-sided design
Trailer wiring tester plug is suitable for all types of trailers, including ship trailers, horse trailers, ATV trailers, and freight multi-purpose trailer coupling devices