The GhostPillow has many unique and special properties. The Gel Memory Foam is aerated and has a top layer of phase change material. There is a 100% cotton inner cover and a dual sided outer cover. All these components work together to provide perfect support for your head, neck and spine. The foam adapts independently sensing the weight of your head and the heat from your body and gently molds to you. The aerated foam in addition to the phase change material keep the sleeping environment cool and comfortable.