Received this well within the delivery time, looks like it came from Belgium as well.
Have managed to try these out just the once at the moment and it just so happened to be raining as well (light rain), seemed to work perfect and constantly (flashing), even at my speeds (average 13mph, max 24mph) and stayed on, though I have used a small cable tie on each one as added security.
Product made in China and quite well made, not sure how waterproof they really are, I guess only time and the British weather will tell!
Quite bright flashing blue and red LED's on both sides, which were noticed, as a work mate mentioned them later.
I believe there fully light activated, they certainly seem to light up most times I even walk pass them at home!
There a little fiddly getting on and clip on the spokes, so that's when I added the small cable tie on each, especially as I think it might attract the 'tea leafs' when no one is looking!
Was smaller than expected as well, about 60mm long and uses 3 x AG3 button batteries each, best place to buy is from the pound shops (about 12 on a card for £1).
No real instructions on the card they came attached to and I guess the name etc doesn't translate too well, 'Alarm Light Of Bicycle' and' Take not to safe' ?
Having said all this, you can't moan at the price, with batteries and so far there better than any 'tyre valve' ones I have tried.