I got these to replace some existing lights with broken lenses. The originals were on a section of the roof that has a sharp curvature to it unfortunately, the bases on the new lights are too thin to accommodate the curve. But luckily the lenses are the same shape as the originals and I was able to use them with my original basses and also I was able to upgrade the original incandescent light bulbs with the new LED light bulbs. For most applications, these bases will probably work fine.