Features: Comfortable grip, strong impact resistance, fall prevention, dust prevention and waterproof. Brake fluid detection is based-on the change in conductivity to determine the moisture change brake-fluid. It shows clearly the extent of moisture contained by the light-emitting diode, high moisture content will lead to lower boiling-point, affect-braking performance. This auto-brake diagnostic testing tool can check the health-status of DOT3, DOT4, DOT5.1 car brake fluid, helps-you to avoid traffic accidents, provide you with a comfortable and safe driving. This check engine is small in size and easy to carry. Press the button and insert it, you can see the result of water content in your brake fluid. This brake fluid-detector is widely used in most car, and it is suitable for detecting the moisture content in DOT3, DOT4, DOT5.1 brake fluid. This product has no-cable connector, it is convenient and easy to use. It can be used in personal-cars or repair shops. Specifications: Material:ABS Size:Approx.15.59x5.51x2.38cm/6.14x2.17x0.94inch Color:Gray+Black Temperature:-10℃-50℃ Test Range:DOT3, DOT4, DOT5.1 Package Includes: 1x Brake Fluid Tester note: ①.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. ②.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understandings.