Great idea, but sorry, I'd never install this device. Why? It clearly states in my vehicle's owners manual that tampering, modifying or removing safety features such as airbags, seat belts, etc. will void my warranty. The legal ramifications of who might be at fault in the event of an accident is staggering and a field day for lawyers.

all I remember is many people in Holland don't wear a seatbelt because of this, great invention

"For most of us, chances are that we will never be in a car that plunges into the water. However, if you consider yourself “at risk” for that sort of eventuality – say, if you’re a rally driver or Jason Bourne."
I heard somewhere; possibly on Top Gear; that more people drown in cars than in swimming pools.

Now add struggle to the equation. Does it still work if it is being pulled on?

Almost $40 for this? You're better off buying one of those emergency tools like the CRKT ExiTool, which has a belt cutter, glass breaker and an LED flashlight. And it's less than 1/3 of the price. You can even use it on more than one seat belt. Plus it would also be useful in other circumstances that don't involve water when the belt might jam, such as in a plain-jane car crash.

This is about time some one thought of this. Good for them.

Yeah sure, be caught in a downpour of a cloudburst with the sunroof's pants down!

Seems like a good enough idea, I would hope they would come standard or something eventually though, as I would surmise most people wouldn't expect to be in the sort of accident that would require one enough to take the time to actually buy one. At least not where I'm from. Having had family perish in this sort of situation though, I can certainly see the merit in the tech.

@ farenheit 451 I don't think this would count as modifying anything, as it's an attachment, though, would it? I don't think you have to remove or add anything to the seatbelt itself.

This was a winner on the show "Het Beste Idee van Nederland" (Holland's Best Idea) back in 2007. Good that they're ready to roll it out now. Statistics for Holland were about 750 cars a year in the water, in which about 50 people drown, most of whom had their seatbelts on.
It'd be nice if this eventually becomes standard.
And for the record, almost everyone I know wears a seat belt, here in Holland.