The case of the DV1 is made of 316L stainless steel, very chunky and actually very well machined.
The red button is actually the helium escape valve which opens automatically when need. The water resistance is a whooping 1000M so basically all water activities this watch will withstand without a problem! On top of the watch sits a flat sapphire crystal with AR coating.
This review is extracted from kaminskyblog.com