I am not a native speaker, hope I read it wrong but I understand it is a patented feature which locks the caseback in two possible positions - either "Diver 300m" writing lines up to 12 o'clock or lines up to 6 o'clock.
I hope I got it wrong as it sounds like super BS.
As much as I like the display backs on these, having the NAIAD to align the Hippocampus on a more toolish design like this would be perfect. Definitely on my radar though, curious to see how it wears in relation to the smaller SS cases.