The pillow has a zip to enable you to individually adjuste the pillows hight and firmnes. The buckwheat hulls comes from organically grown buckwheat, to use the hulls means we are using more of what is already produced. Pillows filled with buckwheat hulls are cool and stable, you can easily give the pillow the shape you desire, it will not collaps nor try to regain its original form, it just adjusts and supports your head and neck.