Car 2 in 1 Diagnostic Tool Brake Fluid Liquid Tire Pressure Tester 1. It is a highly accurate,easy to use, very beautiful product. 2. The tester is a new high-tech product that combines automotive brake fluid testing and tire pressure testing. Users can regularly check the water content of the brake fluid of the car, making driving safer and more worry-free Using the right tire pressure can give you greater safery, longer tire life and better fuel consumption, and hope it will protect your safe driving. 3. Enter tire pressure test: (1). Press the UP key to start testing the tire pressure. The pressure nozzle is pressed against the tire valve,The measurement results appear on the LCD display. (2). Read the tire pressure directly on the display. (3). Press the UP button continuously to convert the measurement unit. (4). Press and hold the UP button for 3 seconds to turn off or Press the DOWN button to close. 4. Enter brake fluid test: (1). Press the DOWN button to light up the green light and start testing the moisture content of the brake fluid. Open the bottom cover of the product and immerse the metal probe in the brake fluid. Within 1-2 seconds,the test results will be displayed correctly. (2).Automatically shut down after 7 seconds of testing. 5. Indicator description: Green light: Battery OK, the water content in the brake fluid is 0% Yellow light: The water content in the brake fluid is less than 2%, which means that the brake fluid can continue to be used for 6 months, and then tested again after 6 months. Red light: The water content in the brake fluid is more than 3%, indicating that the brake fluid cannot be used any more and needs to be replaced immediately. 6. Attention: (1). When measuring tire pressure, the display shows OL,indicating that the test pressure range is exceeded.Press the nozzle firmly while testing, otherwise it will deflate. (2). Press the UP or DOWN keys. The display shows LO,indicating that the battery is low and needs to be replaced.