Easily covered my 10x10 grow tent!!Just bout this and start to use it.Arrived in Canada before the estimated arrival date. I am using them outdoors to provide extra light (for six hours) to areas of my garden that only get 3 hours of direct sunlight. I set them at a distance of 1 foot from the plants which gives me approx 456 umols/s/sq meter. After 4 weeks I am pleased with the results. Since my original purchase of two strings I have added two more strings. I will use them indoors during the winter and spring. The 24 lights cost me 42 cents (Canadian) per day when used for 6 hours during off peak times. Our Ontario Hydro rates are based on "time of use", with 7pm to 7am being the off peak time.So far the lights are working great - they were easy to install and I had no problem with the bulbs lighting up as some have mentioned - I just made sure the bulbs were well seated in the socket per the instructions. The cable is thick and looks to be of good quality. The customer service is outstanding - when I received the grow lights one of the bulbs was damaged at the base. I contacted Espird customer service and described the problem plus provided them with a picture of the damaged bulb. They got back to me right a way, apologized for the inconvenience, and promptly sent me 2 replacement bulbs. I can't yet say how well they will work with the plants since I just installed them - but it looks like the plants are receiving plenty of light. I installed these in a 12 foot by 9 foot greenhouse and they sure light up the interior. So far I'm very pleased with this purchase.Lights are just fine but the timer doesn't work. They sent a new one and it still didn't work after a day. Yes, directions were followed.I am very happy with the product. I had issues with the lights initially, but I received another set of lights free and are working very well. Excellent support..I have a 10’x20’x7’ green house and I was potentially worried about the light coverage these would provide. The photos I could find were all outdoor use and hard to gauge how it would perform in a more closed off space.I installed the light bulbs easily. You do have to make sure to torque down enough to get a tight seal for the water proof aspect of the product. I did not have the trouble some others mentioned. But I did keep the lights in doors until I was ready to install. Which kept the plastics warmer and more mobile because the bulbs are a tight fit.Once installed the greenhouse was so bright. Literally looks like the middle of the day even though it’s pitch black out. As I walked around the greenhouse I noticed my shadow was minimized due to the sting of lights ahead of me and behind me. This will aid in the minimizing of plant shadows as they grow.If you’re on the fence just go for it. So far super happy with the product and will buy again when I get another greenhouse.