MILLY Structured Midi Dress in Black. - size L (also in ) MILLY Structured Midi Dress in Black. - size L (also in ) Cotton blend. Dry clean only. Unlined. Back slit. Exposed back zipper closure. MILL-WD791. 187 JK 120003. The MILLY collection epitomizes bold, advanced contemporary fashion with a feminine edge. Designer and founder Michelle Smith transforms classics by merging American sportswear silhouettes with distinctive Parisian atelier techniques. Smiths eye for impeccable detail, use of luxurious, cutting-edge fabrics and precise tailoring have made MILLY a cult favorite across the globe.