Manipulate the large second hand and cooperate Using the 9 o'clock dial to precisely depend the seconds 100M Waterproof: Which has a h2o resistance of around 100M you can easily cope with most cases in everyday life, like washing palms, rain, swimming(please tighten the crown when likely in the h2o). https://www.watchesworld.com/a-history-of-watch-reference-numbers/