The Casio G-Shock G-Steel GST-W100G-1BER is a men's watch that gets its power from light. This means you'll never need a new battery. The watch has a digital quartz clock that shows time with fluorescent hands. The smaller chronographs show the weekday and date. In addition, you can also set an alarm, timer, or stopwatch. You can choose to turn the sounds on or off. Do you want to be able to read the data clearly even in the dark? Don't worry, a light wrist movement will automatically turn on the LED light in the watch.