We can't emphasize enough how important pillow protectors are to the longevity of your pillows. Our pillow protectors are very specifically designed to protect the investment you have made in the quality of your sleep while impacting the performance of your pillow as little as possible. We do that using very high-end light weight fabric, long staple Egyptian cotton, in a very specific weave that allows the luxurious Hungarian goose down within your pillow to breathe and prevent the yellowing and staining of the long staple Egyptian cotton shell. (with one exception). They provide a very import layer of protection.