Our White Mountain Textiles cotton comforter dust mite covers are some of the nicest we have felt and are very reasonably priced. The cotton fabric is soft and lightweight and offers a very small pore size 4.39 micron, which is excellent for a woven dust mite cover. An encasement with a small pore size like this is a very effective barrier to dust mites and their allergens (i.e. broken body parts and feces). One of my favorite things about these covers is they are discrete and quiet under your bedding, so your family and guests will never know you have dust mite covers on unless they peak under the sheets. They are also very breathable and will not retain excess heat while sleeping. These covers are easy to wash with durable construction; however, we do not recommend washing more than absolutely necessary due to the fact that woven fabrics loosen with wear and tear.