Osram Lumilux Mini tubes are fluorescent tubes designed to fit small spaces, like built-in fixtures in closets. These small tubes have a G5 fitting and a diameter of 16 mm. The length of a fluorescent tube is connected to its wattage usage. So when purchasing a new Osram Lumilix Mini, make sure to choose the right length. Choose the same color as your current light source to keep the same light effect.