What is the main purpose of the marker lights fitted on a truck?

Question

DentroTest · Accepted Answer

The specific function of marker lights is to indicate the total width of certain vehicles in order to clearly warn the other road users of their size. Installing them is mandatory on vehicles whose width exceeds 2.10 meters (and optional between 1.80 and 2.10 meters). They emit white light toward the front and red light toward the rear, and are located as close as possible to the upper outer edge of the vehicle. Therefore, they are not designed to mark the length of the truck (a function entrusted to the side position lights or side reflectors) nor the individual dimensions of the load.

What is the main purpose of the marker lights fitted on a truck?

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