This is a Marc Jacobs shirt. Of course, it is authentic. The color is light blue, and the material is 100% cotton. The size is L, and the flat measurements are: length/approx. 93cm, width/approx. 68cm, shoulder width/approx. 55cm, sleeve length/approx. 64cm. It has been used, but it can still be worn. This is a highly recommended item for those who fit the size. Notes Due to work, email replies may be delayed. Please understand. There may be some slight fading or stains. Please understand that there may be minor scratches or stains that may occur during storage. Comments Please feel free to contact us if you have any questions.