This Organic Cotton pillow encasement pair by Sleep and Beyond is an innovative 100% organic cotton two layer jersey that offers a zippered waterproof solution. This encasement can prolong the life of your pillows and protect them from stains, leaks, dust mites and bed bugs all in one! Free of vinyl/PVC, phthalates and other harmful chemicals, it is crafted with two layers of soft 100% organic cotton jersey fabric with non-toxic TPU inside to provide waterproofing. Pore size of TPU is 3 micron. It is lightweight and easy to wash and refresh!