3 Answers

http://www.instrumentationtoolbox.com/2013/10/how-to-size-orifice-plate-flow-meter.html#axzz40bezHjcX

All of the OP models, no matter the size, do share one dial characteristic. For years, Rolex manufactured its blue-chip watches with a (fittingly) blue luminous material called Chromalight, all link the while continuing to produce the OP line with green Super-LumiNova. With this refresh, you'll find the familiar link blue glow has made its way onto the dials of all five size options link – and it's about time.

I certainly didn't create this mod and I am sure that many of you already do this to link your NATO straps but on the off chance that some of you have yet link to make the cut here is this not-so-revolutionary but hopefully helpful tip. Keep it link breezy and be sure to NATO whenever possible.