Western European solar watches can be left in the sun for 2-3 hours and cannot be exposed to the sun. Generally speaking, direct sunlight is the most effective charging method, but be careful not to expose the solar meter to extreme temperatures. This could damage the components.
The Western European solar watch can be used for 5 months when fully charged and not exposed to light (uncharged) [on average, the electronic sound is emitted for 10 seconds and the The radio wave is received once a day]. However, when there is power when there is no charging, the Casio solar watch charging system is different from the charging system of mobile phones and it will not be fully charged in a short time. Therefore, please refer to the instructions and do not let the Casio solar watch be undercharged. It is very important tocharge frequently.