The OTT units are hyped up by ophthalmologists and others and not worth the price you pay. The ballast is junk and may outlast the lamp as did my MIL's. I can't find any way to replace the ballast or find a suitable replacement for it anywhere. I've gotten better reading lights for less money @ IKEA. Problem there is that you can never get the same one twice as they keep changing them every six months.