What does the small round mirror in the reversing mirror do?

Look at the rear tires and the nearby roads. When reversing, you can see the distance between the rear wheel and the curb in this small mirror, which is not too close or too far from the curb. Most importantly, you can also see the dead angle that the rearview mirror can't see. \ x0d \ x0d \ Small round mirror is convex mirror, also called wide-angle mirror, reflecting mirror and rotating mirror. It is mainly used in various bends and intersections, which can broaden the driver's vision, find the vehicles opposite the bend as soon as possible and reduce the occurrence of traffic accidents. It is also used to guard against theft and monitor dead corners in supermarkets.