I read the reviews before buying and despite the negative I went ahead and bought. I'm very glad I did this. All units worked as advertised. I warn you that the material of the inner metal sleeve is very delicate. Just take your time to screw in the bulbs. Also, on devices where the center cartridge didn't work, I had to take a toothpick and pry off the copper metal tab. This enabled us to establish good contact. Very happy with the amount of light it emits.