I've had an orange one of these jars for a couple of years now and have got really used to it lighting up on the windowsill in the summer; a lovely orange glow that comes on at dusk; so when asked what I wanted for my birthday I decided to get a blue one too. On arrival I was impressed that build quality seems to be better than it was: The jar has a more uniform matte finish and the rubber seal is much improved, it might actually be waterproof this time! Evening number one went well, it was disappointing that it needed to be much darker for it to switch on than my amber jar but I'm sure we could fix that with some tape on the light sensor and the single blue LED is very, very bright; almost too bright actually, but on evening two things started to go wrong: The light came on, but then quickly dimmed and then began this bizarre bright flashing at about 1Hz. We tried turning it off and on again, even opening it and removing the battery to reset but the problem remained. This fault repeated over the next few evenings so we returned the item. I would not buy another, the circuitry needs to be improved.