I got tired of looking for "in between" lightbulbs for multiple ceiling fans in our house - and at the same time I switched all our light fixtures to LED lightbulbs. I couldn't find intermediate base LED bulbs anywhere in the world! Then I accidentally found this adapter. They are a great solution. I have them along with LED bulbs. Now I have a much brighter and more efficient light! And no more looking around and paying ridiculous prices for intermediate cap bulbs!