Two modes for accurate results for athletes and non-athletes. Additional body mass index reading provides added tracking ability.   Application: • Keep one part of head holder on the front side of neck and other on the back side. • Caution: - Use this product under the guidance of a physician or qualified doctor - Discontinue use and seek guidance of a qualified doctor, in case of: - Impaired sensation - Impaired blood flow • Product Care: - Hand wash with mild detergent and water at room temperature - Dry in shade on a flat surface - Do not dry clean