
Amazon.com: G-Shock Casio Mens Watch - 20 bar Water Resistant, Shock Resistant, Magnetic Resistant, LED Backlight, Timer, Stopwatch, Multi-City Time, 12-24 Hour Format : Clothing, Shoes & Jewelry,

Amazon.com: G-Shock Casio Mens Watch - Black - 20 bar Water Resistant, Shock Resistant, 7 Year Battery Life, High Brightness LED Backlight, Timer, ,

CASIO G-SHOCK 4778 AW-591-2A Water Resistant 20bar World Time Wristwatches B4276,

VINTAGE 20BAR-CASIO CHRONO G-SHOCK WRIST WATCH -5229-GA-200BW_CALENDAR FOR MEN | eBay,

What features does this watch have that I may not be aware of? (I got this a while ago and I don't really know much about how to use it) thx in