All you have to do is completely immerse the 2 probes in the brake fluid to have an immediate result displayed by a system of 5 colored LEDs. Easy to use, reliable and fast. It allows you to test the brake fluid, allowing it to be changed only when it is really degraded. 3. principle of operation: Senses changes in conductivity to determine the level of humidity in the brake fluid. Less than 1%: The light indicates that the moisture content of the brake oil is less than 1%, the brake fluid has a good performance. Up to 2%: The light indicates that the moisture content of the brake oil is less than 2%, the brake fluid can still be used. From 3%: the light indicates that the humidity content of the brake oil is at least 3%, it is time to think about replacing your brake fluid. From 4%: the l.
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