We don't have an outdoor outlet near our table and only had an outdoor spot light for light.
These were basically the only battery operated umbrella lights that I could find. Product shipping in a timely matter.
They come with twist ties to tie each strand to the umbrella, but I simply twisted them around each spoke. Recommend taking the umbrella down (as the instructions say to do).
The light is much better than I expected. it's not too bright, but I like that you can see people you are talking to in the darkest part of night. You can also close up the umbrella with the lights still attached.
I would say the only cons are the battery pack not having a switch (you have to unplug the unit.
A little trick, I did was attaching the battery pack at the top (above where the "hub" sits when the umbrella is up. You attach the battery pack via a large twist tie. I attached it a little loose so that when I lower the umbrella, the battery pack slides down with it and I can unplug it without getting on a chair. Just open the umbrella slow and push the battery pack up when you want to use it.
Overall, very satisfied.
We sell a lot of these lights. Some people love them, others not so much. We have taken a few returns on these because customer didn't understand they were batter operated, or they were difficult to install. They are designed for 9' umbrellas but you can put them on larger or smaller umbrellas if you are creative or don't mind them not covering the entire umbrella. They don't put out a lot of light but enough to eat under. I would recommend using a different kind of zip ties then provided with the lights. The ones supplied are cheap and don't hold very well. They are also available in 110V version.