Ergoflex Massage pillow design is best for side sleeper. It helps ensure proper support for the neck and shoulder throughout the night. In one pillow there are 2 different heights of 10 cm or 12 cm curvature, with ventilation air flow holes. Choosing the height of pillow depends on the different gaps of the neck’s C-curve in each person and your preferred comfortable sleeping position. The extraordinary feature of this pillow is the knob ‘massage’ surface designed to help increase blood flow to the brain for fresher start in the morning. Similar to Ergoflex, the inherent quality of Latex is that it is naturally resistant to dust mites, mold and bacteria, making this Latex pillow totally hypo-allergenic, and toxic-free.