The Casio G-Shock Black Octagon Smartwatch GA-B2100-1A1ER combines a 45mm octagonal shaped plastic case and black plastic strap with a traditional buckle. It has a black plastic dial with luminescent hands, date display which is protected beneath mineral crystal glass. Power is generated by the quartz movement. Other features include an alarm, a back light. This model also has a water resistance of up to 100 metres. Accuracy +/- 15 seconds per month Alarm function Hourly time signal: The watch beeps very hour on the hour Automatic calendar Once set, the automatic calendar always displays the correct date. Battery level indicator An indicator shows the current battery level. Bluetooth Connectivity Connect to compatible smartphones for a range of features Core guard structure Four stainless steel pipes form a metal frame that joins the bezel securely with the case back for increased shock resistance Countdown timer Countdown Range: 60 minutes, Measuring Unit: 1 second Date and weekday display The current date and week day are displayed on the watch face Display illumination Auto Light: The watch dial will illuminate automatically when you tilt your wrist towards you. Once activated, this feature will automatically deactivate after six hours. LED light selectable illumination duration (1.5 seconds or 3 seconds) Hand shift function With a push of a button, hands move away to permit free visibility. Multi-language display Allows the day of the week to be displayed in a number of different languages Mute function The button tones on the mode button can be switched off for discreet operation. Pre-set alarm or timer functions remain active. Neobrite A luminous coating on the watch hands provides illumination in the dark. Shock-resistant Shock-resistant construction protects against impact and vibration. Solar power A solar cell provides power for operation. Stopwatch function World time function Displays the current time in major cities and specific areas around the world. "Timer - 1/1 min. - 24 hours Countdown timers help you to remember specific or recurring events by giving off an audible signal at a preset time. The time can be set to the nearest minute and up to 24 hours in advance. Ideal for people who need to take medicines every day or those who do interval training."