This sheer lingerie one piece has elasticity and can fit a variety of sizes. It can be worn as lingerie or worn matched together with other garments and worn as a dress. The size 1X can fit a size medium to a size 1X, depending on desired fit. The model is wearing a 1X. The mannequin is made to fit size medium apparel. The 5X can fit a size 2X to 5X, depending on desired fit.