Philips Hue White Ambiance reflector LED bulb GU10 4.2 W, set of 2; Philips Hue White Ambiance 4.2W Bluetooth GU10 LED bulb, 2 pieces. Useful information When buying a new LED bulb, there are a few things you should keep in mind. The strength of an LED bulb is measured in lumens, not watts. 15W = 140 lumens 25W = 250 lumens 40W = 470 lumens 60W = 800 lumens 75W = 1050 lumens 100W = 1520 lumens In addition, each traditional light bulb has an RA or CRI value. This describes the traditional light bulb's ability to reproduce colours and is measured on a scale of 0-100 CRI, with 100 CRI corresponding to natural light. For normal households, we recommend using a traditional light bulb with a CRI value of at least 80CRI. Kelvin degrees, on the other hand, describe the warmth of the light. 8,500 - 10,000 K = Cold blue 7,000 - 8,500 K = Cold white/blue 4,500 - 7,000 K = Cold white 3,000 - 4,500 K = cool white 1,000 - 3,000 K = Warm white For comparison: Candlelight has a Kelvin value of about 1,500 K, direct sunlight is about 5,500 K, and a blue sky can reach 10,000 K. material: plastic
