These Opus G9 mains voltage 240volt Eco energy saving dimmable halogen capsule lamps, are designed for domestic household and commercial environments, and are a direct replacement for existing G9 2 prong/loop cap types. Typically these compact lamps are used in ceiling lights, desk lamps, side table lamps, chandeliers, cooker/extractor hoods and many more fittings with a G9 lamp holder. Using only 28watts, with an output of 370 lumens they are an ideal replacement for 40watt standard halogen capsules.