All-Natural Buckwheat has been used as bedding in Asia for hundreds of years. The tiny hulls, no bigger than 1/3 or less of your baby-fingernail, are hollow, since the farmer has already removed the seed to be ground into buckwheat flour. So you have a tiny, jagged, hollow hull, or husk, that has a slight resilience to it. These hulls, when manipulated within the pillow, cling and grab together, and thus, as you shape the pillow for support and sleeping, the pillow stays where you put it! It doesn’t just sag down the minute you get comfortable. This is why they work so well – the pillow stays where you put it.