This season's sold-out balloon sleeve denim shirt. I think a size S would be fine, even if you usually wear a size M. Here's the product description: Shirt made from a denim blend of lyocell and cotton. Features a collar and snap fasteners at the front. Includes a back yoke. Long balloon sleeves with snap fasteners at the cuffs. The hem has a gentle rounded cut. Size: Shoulder width: 41.0 cm (size M/T), Back: Length: 62.0 cm (size M/T), Sleeve length: 63.0 cm (size M/T) Length: Regular length Sleeve length: Long sleeve Fit: Regular fit Collar: Turn-down collar Sleeve style: Balloon sleeve Description: Dark denim blue, Solid color Material Ingredients Cotton 48% Regenerated fiber (Lyocell) 52%