Just thought I'd do a bit of 'satisfied customer' feedback here.
I bought 3 of these for the family lifejackets having been out a few times in the dusk - twilight recently. My jacket was already fitted with one but the others were not. Into the night, lights are essential in my opinion even if the lifejacket has reflective bits on etc. These lights are about the best on the mkt I believe but are pretty pricy at retail for what they are.
Anyway, as advertised, new lights with long life. nicely delivered at a good price for ribnet folk. Strange to admit for something you really hope to throw away unused in 5 years time - a bargain - seriously.