Really? I thought that getting on a submarine was suicidal. Go figure. Boats actually work?
Yes, but the fan itself must still be exposed. And it’s a moving part. Unless the fan shaft is physically isolated from the internal motor, it’s going to provide another area of weakness for water to get in.
I’m waiting to see someone torture-test this thing under water. I’ll bet it’s not as water-tight as a regular flashlight, especially while the fan is on (though maybe they’ll automatically turn it off).