Description: Strong temperature resistance and good performance make it very reliable and useful. Simple and convenient operation will not waste your time and energy. The light weight and small size make it very convenient to carry and store. And the fine and professional workmanship allows it to be used for a long time. Made of plastic and metal, it is very durable to use. The length of this product is 13cm and the width is 6.8cm. This relay tester is a quick test tool to test automotive relays and let you know the status of automotive relays. By connecting the car battery (11V-15V) to the relay coil, the tester can properly check the relay contact function. The tester will observe the contact data, the closing time, the inertia of the relay in each test phase, and so on. If the test is passed, the green light will be on, and if the test fails, the red light will be on. Item Name: Automotive Relay Tester Material: Plastic, Metal Features: Quick Test, Effective, Easy Operation Size Details: Size: 13cm x 6.8cm(Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. The car battery must be a 12V battery, and the voltage must be between 11-15V. The coil resistance is preferably above 20 ohms. Package Includes: 1 x Automotive Relay Tester 1 x English User Manual