1. To check the quality of brake fluid.
2. 5 LEDs to indicate percentage of water in the brake fluid.
3. Battery= 1.5V AAA.
4. Suitable for DOT4.
5. CE and RoHS approval.

Green: battery OK, i.e.: no water contained in the brake fluid
Yellow: less than 1% of water content in brake fluid
Yellow/yellow: approximately 2% of water content in brake fluid
Yellow/yellow/red: approximately 3% of water content in brake fluid
The brake fluid should be changed
Yellow/yellow/red/red: at least 4% of water content in brake fluid
The brake fluid must be changed urgently, extreme danger