Part of a diamond plate.
Diamond plate also known as fluted plate or diamond steel is a type of metal plate usually prefabricated which has a regular pattern of "diamonds" or raised lines that allow a better grip thus avoiding the risk of landslides. It is usually made of steel or aluminum. They are widely used in ladders and industrial walkways, as well as in floors and mining facilities. They are also used inside ambulances and on the sides of fire trucks. It can also be used merely decorative.
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