Design
Philips
Concept
Light bulb LED 7W (621lm/50W) Dimmable 36° GU5,3
Useful information about light bulbs
When buying a new LED light bulb, there are some important things you should be aware of.
The brightness of an LED bulb is measured in what is called lumen instead of watt.
15W = 140 lumens
25W = 250 lumens
40W = 470 lumens
60W = 800 lumens
75W = 1050 lumens
100W = 1520 lumens
In addition, a RA- or CRI-value is also stated on the light bulb. It describes the light's ability to reproduce colours and is assessed on a scale of 0-100 RA, where 100 RA corresponds to daylight.
For a typical home, it is recommended to use a light bulb with an RA value of min. 80 RA.

the Kelvin rating, on the other hand, describes how warm the bulb's light is.
8.500 - 10,000 K = Cool blue
7.000 - 8,500 K = Cool white/blue
4.500 - 7,000 K = Cool white
3.000 - 4,500 K = Neutral white
1.000 - 3,000 K = Warm white
In comparison, the light from a candle has a Kelvin degree of approximately 1,500 K, direct sunlight is 5,500 K, while the blue sky reaches 10,000 K.
If you want to know more about light bulbs you can find more information here.