Setting Modes: System Sound Settings: ON to turn on the alarm sound/OFF to turn off the alarm sound. Speeding reminder: alarm when the vehicle speed reaches the set default value of 150km/h, the setting range is 5-200km/h. Engine temperature alarm: alarm when the water temperature reaches the set default value of 120, the setting range is 50-200. Engine speed alarm: alarm when the speed reaches the default value of 6000r/min, the setting range is 1000-8000. Voltage alarm setting: alarm after the voltage is lower than the set default value of 10.5v, the setting range is 10.0-15.0v. Speed error adjustment: adjust the parameter value when there is an error between the speed and the instrument panel (for example, the instrument displays 100 Km/h, the device displays 105 Km/h, and the dial wheel is turned up to adjust the parameter value to 102). Speed zero setting: when the vehicle speed does not return to 0 after the car is turned off (for example, the vehicle speed displays 5Km/h and the device is adjusted to 6Km/h). Voltage error adjustment: when there is an error between the voltage and the instrument panel voltage, fine-tuning can be done (for example, when the device displays 0.2V higher than the instrument voltage, the device is adjusted to 98%). Engine displacement setting: When the fuel consumption error is large,adjust it according to the displacement(for example,if the displacement of the car is 3.6L, adjust the parameter value to 3.6L).Adjustment of fuel consumption data: fine-tuning when there is an error in fuel consumption (for example, when the device shows 0.2L higher than the meter voltage, the device is adjusted to 98%)Backlight brightness setting: Auto auto-sensitivity,1 is the darkest, 8 is the brightest. Ambient light settings: RPM speed control color-changing ambient light SPEED speed control color-changing ambient light. OFFTurn off the mood light BLUE blue mood light RED red mood light mood light. Shutdown delay setting: the default is 10 seconds to shut down, the adjustment range is 5-300 seconds. Shutdown voltage setting: adjust to 13.2V or 13.6 when it cannot be turned off, and adjust to COM mode for cars that automatically start and stop. Restore factory settings: The system is restored to the factory default value After selecting this operation, short press the M key to confirm. Calibration of the incline meter: short press the or button after the meter is placed: when you hear the beep, the calibration is complete. Operate: 1. Left ambient light: change with engine speed or vehicle speed (setting items can be ) 2. Power button: long press for 2 seconds to turn off, long press again for 2 seconds to turn on 3. Left button: short press to switch the display on the left, enter the setting and then move the option, and short press the calibration on the display interface of the incline meter 4. Right button: switch the display on the right, and move the options after entering the setting 5. M key: short press (press once) to switch the display mode, enter the setting menu to confirm the option Long press (press and hold for 2 seconds) to enter the setting, after adjustment, press and hold for 2 seconds to save and exit 6. Right ambient light: change with engine speed or vehicle speed (setting items can be ) Colour:Black Material:Plastic Package Contents: 1 x P21 Host 1 x OBD Cable 1 x Bracket 1 x Double-sided tape Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.