... difference.2. Daylight, coolwhite, and warmwhite are optional for differenct requirement on color temperature.3. Advanced water-powder ... temperature -15`C-50`C,the best operation temperature for illumination will be 35`C.6. High lumen ... enhancing light output,and effectively saving energy, especially for HE,HO series.8. Suitable for offices, marketplaces, supermarkets, households, schools, exhibition ...