Warming button is used to adjust water temperature through elevating water temperature. Cooling button is used to adjust water temperature through decreasing water temperature. Ozone control button is used to control the on-off of ozone generator from which the ozone water produced has disinfection and sterilization effect. Power button is used to control the beginning and end of the whole procedure of hydrotherapy. Best Regards, The Export Manager Strong Lau / 13713905143 Email: sound3w(at)126.com website: Http://sound3w.en.ec21.com Tel: +86-755-82266854 Fax: +86-755-82402546 Add: 6/F, East Building 2, Guangxian Subdistrict, Bagua 3 Road, Futian Dist, Shenzhen. China.