Using a fabric developed for NASA to help astronauts adapt to extreme temperature fluctuations, this comforter prevents overheating and eliminates chills to create an optimal sleeping climate. Embedded in the comforter's shell are millions of invisible microcapsules that absorb excess heat when you are hot and release the stored heat when you are cold, ensuring a comfortable bed temperature and humidity. Unlike an electric blanket, the microcapsules adjust independently to an individual's climate, allowing two sleepers with different temperature preferences to remain comfortable throughout the night. The 350-thread count exterior is made from 100% cotton and the comforter has 31 oz. to 54 oz. of polyester fiberfill, depending upon size. King. 108" L x 98" W. (6 1/3 lbs.)