Review on Efficient Recessed Downlight Installation: Sunco Lighting Industrial Electrical Components for Lighting by Michael Tran

We couldn't figure out why some of them wouldn't work when screwing the end in, but found out after we installed about the 8th time - the end was plastic a coating that prevented some of them from making a good connection. After we removed the coating with a scraper, they worked without any problems. Nice bright light! For a change, we can actually see well in the kitchen! Update: After having them on the ceiling for a few months we had to replace them all. They all started flickering - not a dramatic flicker, but enough to give you a headache if you're in a room with the lights on for any length of time (which is especially the case when it's getting dark). We would not recommend them at all.