Feature: 1. WORKING PRINCIPLE: The brake fluid liquid tester uses the change of conductivity to determine the moisture content of brake fluid, enables for DOT3 DOT4 DOT5.1 types. 2. HIGH PRECISE PROBE: Equipped with a high precise probe, the brake fluid tester pen can provide accurate and reliable test results for your vehicle safety. 3. WATER CONTENT DETECTION RANGE: Detects moisture content in the range of 0% to 4%, allowing car owners to quickly determine whether their brake fluid meets standards. 4. SOUND AND LIGHT ALARM: With a sound and light alarm system and red, yellow, and green tricolor backlit display, the brake fluid moisture tester is easy to use and read. 5. ENSURE SAFETY: The brake fluid analyzer is an essential tool to ensure your safety on the road, protecting you and your car. Specification: Item Type: Brake Fluid Liquid Tester Material: ABS Model: AN662 Battery: 2 x 1.5 AAA batteries (not included) Display: LCD Water Content Detection Range: 0%-4% Error: ±0.3% Detection Type: DOT3, DOT4, DOT5.1 Usage Environment: Operating Temperature: 0-40℃ (32-104℉) Storage Temperature: -10-50℃ (14-122℉) Humidity: ≤95% Altitude: ≤2000m Alarm Mode: Sound and light alarm Probe Shape: Flat and long Backlit: Red, yellow, and green tricolor backlit Water Content Indication: The buzzing sound becomes faster, the backlit color changes from green to red, the numerical value displayed on the LCD increases Auto Power Off: Yes (shuts off after 5 minutes of no operations) Low Battery Indication: Yes Safety Level: EN61326-1. Package List: 1 x Brake Fluid Liquid Tester1 x User Manual