"Waterproof" things are typically rated as "waterproof down to 3 meters/10 feet"
That said, WW2 subs weren't really deep-divers, themselves (at least, for submarines), only going down about 300 feet, since they were mostly designed for surface running and only going just below the waves for stealth, not maneuvering underwater like modern subs. Even that was a surprise to the Japanese, though, who needed a media leak to even learn that American subs were surviving their depth charges because the Japanese didn't think American subs would go deeper than 100 feet...
Waterproof
Dustproof
Newest!!Huh...?
It won't turn on...So modern communication devices are waterproof...I'll show the Admiral how the deep sea look like in some pictures
