Wau die sind ja richtig hell......gut

Warm white as a color description is incorrect, these are actually quite blue. From a purely visual judgment, I would say somewhere over 6000K. Brightness appears to be consistent with 300+ lumens. The only real concerns are
1) The thickness, with the cooling fins of the alu housing between the long elements protruding slightly from the diameter of the round fins (12.4 mm). Fitting to a W2.1x9.5d sidelamp housing that is coaxial with a H4 headlamp was very tight.
2) The mass and length (43.2 mm) compared to a W5W is significantly higher, which places more stress to the base. If they are not fully plugged in, they will easily drop inside the headlamp. Only time will tell if the connection to the base needs to be strengthened.

Overall still quite pleased, considering how these are the brightest leds available for this base and in general a non standard item.

The photo shows a comparison with a 2.5W 100 lumen similar technology 4 high power element LED bulb on the left (as viewed from the front) and the subject 7.5W bulb on the right. For brightness and color comparison, the car on the street to the left has filament bulb headlights on (1000 lm, 3200 K).