The architects painted the cables white, so that they would disappear into the sky on overcast days, and complement the blue of clear skies.

WSJ: A Concrete Ribbon Through the Clouds | Millau Viaduct | Masterpiece by Joseph Giovannini

You can choose different colors and mirrored or non-mirrored, but all are packaged with matched low and high VLT duos to cover sunny days, overcast days, and days when you get both sun and late day flat light.

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