Many semi-trucks' front tyres have spikes on the side for no apparent reason.

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Semi-trucks often have metal spikes or spike strips mounted to the side of their front tyres.

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Tyre chains, sometimes known as snow flaps,

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are a type of vehicle accessory that helps increase a vehicle's grip and traction on icy or snowy roads.

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They also help the truck driver keep their footing when the road gets slick from turning or rain.

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The metal spikes embedded in the truck's tyres provide traction,

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allowing it to maintain a firm footing regardless of the road surface.

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They improve handling in turns and increase stopping distances on wet roads.

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