Very contemporary, typical Margiela style design, "horizontal dress" for H&M. The vintage horizontal dress, consist of an A-symmetrical in length, tube dress with, like a sort of giant scarf, horizontal dress, worn horizontally over the shoulder attached to the tube.

Horizontal shirt dress has collar, long sleeves and a wide skirt with zipper in the side and button and button holes.

To put the dress on, you have to put the tube dress over your head, with your head through the side opening of the horizontal dress and let the skirt part, hang on one side over the shoulder and the upper side of the shirt dress, with collar and sleeves, over the other side of the shoulder.

Should you want to wear the horizontal shirt dress, vertical? That's  possible, but then you have the tube dress hanging around as an extension.