Chronofighter oversize big date gmt watches are frequently called the ultimate chronograph the calibre is g1733 automatic bi compax chronograph the watch makes 28 800 vibrations per hour additional functions include incabloc shock absorber 28 jewels and a 42 hour power reserve the chronograph has seconds and a 30 minutes counter other useful functionalities include gmtsecond time zone and a big date window at the 12 oclock mark hands mark hours minutes and seconds