I bought these to plug into 3 outlets in my garage - a two (2) car garage that was complete is painted black (walls and ceiling). 2 lamps were in the middle of the garage and the third one on a wall. I took some UV reactive tape and placed it in the farthest corner of all three lights, and while I could still see the tape, it didn't "pop" or "glow" as expected. As a result, I bought about 20W (2pcs) black LED bulbs from Amazon, which were much better for my purposes. These bulbs just weren't powerful enough to do what I needed them to do, despite their equivalent wattage. So if you're trying to throw a glow party, I wouldn't recommend these lights for a room the size of a two car garage unless you're using about 8 of them in the room (that's a guess). UPDATE 21.07. /2018Adding photos taken with a phone camera (SAMSUNG Galaxy S8+, no flash). The photos show UV reactive tape and UV reactive balloons that I looked at elsewhere. This will show you what the ribbon and balloons will look like when these lights shine on them. Images are labeled to show distance from light sources for reference.
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