What looks like a filament in these lamps at first glance turns out to be a complex construction on closer inspection: a substrate (a glass substrate) is densely covered with a large number of tiny chip-diode pairs, over which there is a fluorescent layer consisting mainly of phosphor. In terms of luminous efficacy, light color and color rendering, the fluorescent layer provides light properties that are very close to those of the standard household incandescent lamp banned by EU regulation. These lamps are also much more energy-efficient and have a much longer service life, making them a fully-fledged replacement for the classic incandescent bulb.