Pellon Home Allergy-Free Pillow Insert, 16\" x 16\" Square Shape. Pellon Allergy-Free Pillow Insert is made with 100% Hypoallergenic Polyester Fiber. The cover serves as a barrier against most common household allergens and irritants. There is a gusseted edge for extra loft and corner support. Customize cushions to match your décor and style throughout your home. These pillows can be machine washed and dried for added convenience and cleaning. The cover is a 250 Thread Count Polyester Weave.