NWOT Free People Happiness Runs Henley One Piece Jumpsuit Size Medium / Large. A combination of two of our favorite Happiness Runs styles, this ribbed onesie is featured in a body-sculpting silhouette that hugs your curves with a henley style top, back cutout, and never see-through knit. Snap button top 7/8 cropped length Entry-level compression 76% Nylon, 24% Spandex