The Bathtub Light has been found to use one of these or at least this type of 4 pin base. Apparently the developer agreed. I was "excited" when I found out that there was a manufacturer for this type of lamp. It's CFL and it starts off pretty quickly. It only happens 2300K, ie cool white. I prefer daylight. They are very expensive for what they are. If, like me, you're stuck with this type of base and don't want the inconvenience of taking out the ballast and converting it to a screw base, this is your choice. I hope this one lasts longer than the 2 years that came with the house. For a CFL that runs 15 minutes a day, that's not very good. Not very good for an incandescent lamp in that regard.
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