This Rolex 126519LN is the white gold Cosmograph Daytona, the brand's racing chronograph in its most precious form, a natural target for the collector who wants the icon in something other than steel. The self-winding caliber 4131, Rolex's current-generation chronograph movement, drives the counters and runs about seventy-two hours. The 18k white gold case measures 40mm across and 11.9mm thick, unusually trim for its type, its black Cerachrom ceramic bezel carrying the moulded tachymetric scale that has tied the Daytona to the track from the start. The black dial sets three counters against applied markers. What sets it apart is the restraint: in white gold it reads almost exactly like the steel Daytona, a watch recognized everywhere, hiding here in plain sight.