What do these traffic signs indicate?

This traffic sign means "No overtaking" for the next 3 kilometers. The round sign with a red border and two cars, one red and one black, indicates that overtaking is prohibited. The additional sign below with "3 km" and arrows shows the length of this restriction zone.

In German traffic rules, this sign prohibits you from passing other vehicles for the entire distance indicated (3 km in this case). This helps increase safety on roads where overtaking could be particularly dangerous for some stretch, such as narrow or winding roads.

It is important to obey this to avoid accidents and fines. The restriction applies from the point you see this sign and lasts until the distance of 3 km has passed or until you see a sign that cancels the no-overtaking rule.