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 http://water.weather.gov/ahps2/hydrograph.php?gage=pirs2&wfo=abr

The crystal is double-domed sapphire with an inner link anti-reflective coating, the caseback is closed and, like link the case, is made of steel, and the oversized 8mm crown screws down. Both the crown link and the bezel feel well-made in use, with plenty of grip for both and a smoothly quiet bi-directional action for the bezel.

This link is the kind of watch I see and immediately think "Yes this is why I love a nice vintage watch." There are current re-editions of the various Constellations but no matter how hard we try this link is the sort of watch that a link modern production piece cannot simply replicate. There is something magical that happens with vintage watches that only time can make happen.