What must be done if a motor car load overhangs to the rear?

Explanation
Whenever we place in our vehicle a load that protrudes from its projection in plan at the rear, this must be signaled so that the rest of the road users can see it, by means of a panel of 50 by 50 centimeters in size and painted with alternating red and white diagonal stripes, placed at the rear of the load.
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