Medslant Allergen Barrier"BIG" Wedge Pillow Cover for the Medslant BIG Wedge Pillow Only The 4 micron weave prevents allergens and dust mites, allowing you to breathe more easily as you sleep. The soft Poly/Cotton cover is washable up to 160 degrees. Fits Medslant BIG pillow ONLY - 28" W x 32" L x 7" H