For persons of weight 65 kgs or smaller and less that height of 5 feet 6 inches, a smaller pillow (Standard Size) is good to go. For persons who weigh above 65 kgs, a larger pillow (Premium LYTE) offers maximum support. The pillow itself should be stationary on the bed once you have decided your sleeping position as per your comfort. The pillow itself should not require any tossing or flipping.