UPDATE: None of the four actually found the lamp to be usable. One of the four was DOA, and all three others emitted a flickering light. Two bulbs that I thought were ok only turned out to be in a well lit room with natural light. However, at night, when they were the only light source for reading, the flickering became apparent and it was impossible to use them. What follows is the previous rating. In my experience rubbish. With two different lamps, 1 out of 4 lamps did not light up at all. (Yes, of course I've tried other bulbs, both LED and halogen, in these lights. Even two of the four bulbs work reliably with two lights.) The second bulb from the box lights up, but gives unusable light. flickering light, no matter what device it is built into. They're too cheap to return, but expensive enough to warn you against buying.
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