Park the car on a level , stick the adhesive on the product, adjust and fix it in the vehicle for easy horizontal view. Before driving, connect the power supply and wait to receive the satellite GPS signal until the data shows normal. Long and hold the setting button and click the start button to adjust the electronic clock. and hold the start button, and click the setting button to adjust the time of the X90. Precisely shows vehicle tilt angle with clear notification, when the angle is over 40°, alarm alerts. Precisely show vehicle pitch angle changes,when the angle is over 40°the alarm alerts to insure your safety. After connected to power supply, there be backlight inside, which help you see accurately in case of night or dark situation. Elevation error within 5- 100 meters. After the vehicle starts the speedometer starts automatically, after car parking the meter be in sleep mode automatically. Over speed alarm. Fatigue driving alarm alerts after driving for 4 hours Power: DC