Ultra thick and supportive: The mattress cover is made of ultra-filled (50% 3D+50% 7D) natural fiber, which is the most advanced natural fiber fabric filling material, ensuring the comfort and thickness of the mattress cover, providing sufficient support for the body, making you feel energetic every morning when you wake up. Compared to traditional mattress covers, it uses 3D velvet instead of padding to disperse body pressure and prevent sagging.