The Rolex fluted bezel is often a mark of difference. Initially, the fluting on the Oyster bezel experienced a purposeful objective: it served to screw the bezel onto the situation helping to ensure the waterproofness of the watch. 36mm: This size is taken into account the common Rolex Datejust dimensions, https://rolex-oyster-perpetual-da37913.bcbloggers.com/30008646/indicators-on-rolex-oyster-perpetual-date-you-should-know