It was lit continuously in 3 months from purchase, it was impossible to switch to blinking and turn off. It seems that contact failure of the switch. As a frequency of use, it is about 20 minutes once every 2 weeks, total 3 hours? Although there was no problem in brightness etc., it is regrettable that we will break down in such a short time. There is no falling or wetting with water. Also, I was exchanging a new alkaline battery twice in the meantime, although the power consumption was also high. I thought that I bought a cheap and good one, but it is a shame. Next time I think I will buy domestic products.