Studio-Assets Muslin for 8'x8' PXB System - Chroma Key BlueStudio Assets Muslin for 8'x8' PXB System Chroma Key Blue This 8 x 8' chroma key blue muslin is for use with the PXB Portable X frame Backdrop System. The PXB Solid Color Chroma Key Blue Muslin Backdrop is constructed from 100% cotton muslin. It is machine washable on the gentle cycle using cold water and a mild detergent. The muslin is mill dyed using reactive dyes and then steam dried allowing it to be lightfast so it won't fade over time. SKU