Main Material --- ABS and CopperQuick Check --- This trailer connector has one side to connect to a trailer's 7-pin plug and another side to connect to a car's 7-pin socket. This tester quickly indicates if there is a fault in the car's or trailer's wiring and effectively tests the problem with 7-pin plug and socket connection.European Universal Standard --- Approved by Europe CE, ROHS certification, ensuring maximum strength and durability for long-term use. Such a practical trailer testing tool you need.Reliable Quality --- 7-pin trailer tester with safe and reliable performance, reasonable design. Skillful appearance, convenient use. The trailer tester's socket is widely suitable for caravans, RVs, campers, vehicles, trucks, trailers, etc. The test requires a 9V battery (not included)High Performance --- The car trailer connector tester is made of high-quality ABS and copper, its frosted surface, durable and reliable, ensures resistance and maximum durability for long-term use. One side connects to a 7-pin plug and the other to a 7-pin socket, can also be used on 13-pin with the adapter. (7-pin trailer tester + 2 x 7 13 converter)