Hard to find in the traditional trade, this adapter purchased from Amazon is perfect to put less energy-hungry light bulbs but equally bright (27 W halogen against traditional 40 W). However, the adapter's base exceeds where it is screwed and reveals the marked text on it (on the other side of the picture). Before buying a ceiling (or other), check that the lighting system that includes G9 bulbs are in line with the proposed system (mostly E14 screw), otherwise you will be like me forced to buy this adapter. Suddenly, the energy saving is gobbled by this additional purchase. Delivery time a bit long for my taste. Otherwise, the adapter perfectly fulfilled its role.