Digital measuring provide quick and easy way to test the presence of water in the brake fluid, specially developed for car users & garage mechanics. Turn on the tester by pressing the up button. The green LED starts to light up. Hold the test sticks up to the plastic for one second in the brake fluid. Then the test result is displayed with the LEDs. The tester switches off automatically after 12 seconds. Brake fluid pen 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. Red indicates the brake fluid needs immediate replacement, green represents good condition, .
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