I have two desktop high intensity lamps - one I bought a few years ago, and one a recent purchase. The older lamp failed about 3 months ago, and I replaced it with the new one thinking the older one was finished. Then when the newer lamp blew a bulb I decided to get a set of these bulbs to see if it would work again. Replacing the blown bulb with a new one from this package took a minute or two (being careful not to touch the bulb with my fingers), and the new lamp was back to working. So I decided to try one these bulbs in my old (presumed dead) desk lamp. After carefully installing the new bulb my old lamp was back to life. They are both still working, and I am delighted with this purchase.