C means that the product is rated in its category in terms of energy efficiency. The Energy Labeling system is based on EU Regulation 2017/1369/EU. C Hama 00232575, 2.9 W, 40 W, E14, 470 lm, Warm white Hama 00232575. Bulb power: 2.9 W, Equivalent bulb power: 40 W, Fitting/cap type: E14, Luminous flux: 470 lm, Light colour: Warm white, Colour temperature: 2700 K