I bought this at COS in London a few years ago. I've worn it a few times, but it's in beautiful condition. It has a pleated design in the back, and the back is slightly longer. It can be worn like a tunic. The material is cotton, and the pleated part is a blend of cotton and polyester. The pleats remain beautiful even after machine washing. The color is a deep navy, which is elegant. There is no size label, but I believe it is a size 34 or 36, equivalent to an XS. I'm selling it because the sleeves are slim and I no longer wear it.