A high density, slow recovery, temperature sensitive memory foam developed for NASA provides exceptional, contouring support. Plus, this amazing material responds to your body heat and conforms to you, relieving pressure areas and improving comfort. Memory Foam clusters are made with the same viscoelastic foam used by NASA. Our unique process utilizes micro clusters to create a luxury pillow that is in balance with the way you sleep. Allergy sufferers love our memory foam bed pillows because they"re naturally hypo-allergenic. This pillow fits a standard size pillowcase.