I am a Dahua CCTV product service and sales representative. I have the Dahua dashcam product available for the first time! But the drawbacks: The camera does not support motion detection mode!!! Which is a big drawback!! When the car is in a private parking lot from night to morning, poor quality images (no night vision) are being recorded!! The camera itself froze and turned on and off twice in one day!! While driving for several minutes, although the recording sign was on the screen, no recording was made! And this is unreliable!! It is unfortunate and such problems from Dahua are unlikely!! The speed displayed in the image is not calibrated! And it shows 8-10 kilometers more!