I've had this set of lights outside twined round a Californian lilac for some time now, and they have been working throughout the bad winter weather; they have stood snow, ice and rain without a hitch, and twinkle very nicely. The different modes are good, though one might be a bit risky for epileptics. The only problem I have had has been when the temperature dropped to ten below, the off switch froze and I had to warm it with my breath for a couple of minutes before I could switch off or on. The battery life has been pretty good, I'm using Duracell plus and haven't had to change them yet; I have another illuminated feature with the same batteries, and I have had to swap those twice over the same period. Good value.