Audible and Visual Dual Prompt: When the water content of brake oil is detected, the display screen and buzzer will give dual prompts. Backlight: Red and green backlight. 1 Brake Fluid Tester Pen. Function Switch Key: After starting, press S key to switch to DOT3/DOT4/DOT5.1, and press S button to switch the brake oil type(default is DOT3).
