Description: The relay quick tester can provide you with the overall operating status and function instructions of the most common automotive relays. After the test contact is closed and opened ten times, the tester will check the consistency of the relay. If the relay is abnormal, the red LED will light, and it's normal, the green LED will light. Car relay tester provides a convenient and intuitive diagnostic way, which is time-saving and economical. Auto diagnostic repair tool is easy to carry, small and compact, you can test it anywhere. Car battery must be 12V battery, the voltage must be between 11-15V, the coil resistance is preferably at least 20 ohms Specification: Material: plastic + metal. Color: Red, Yellow. Voltage: 12V. Size: 11.5x6.6x2.3cm. Package Include: 1 x Car Relay Tester. 1 x English manual"