The XLarge size has been defined by the "regular" size chart used for every product of our assortment and most popular American sizing. The shape is based on the XSmall to XLarge size range, same body fit.
The 1X size is based on the body fit of usual plus size sizing and products. The morphology differs from the XLarge size and follows the 1X to 3X shape.
If you want a size up or a looser fit, consider taking a 1X instead of XLarge.
Products sizes have been designed to be as follows;
Xsmall, Small, Medium, Large, XLarge, 1X, 2X, & 3X.