What people's eyes perceive differs. What may appear to have a "hint of yellow or blue" to one person may be perceived as "pure white" to another.

In addition, manufacturer/brands, headlight style/type, projector vs plug and play, age of bulbs, etc. all play a role in the color output. You may see a 5000k kit that looks a little yellow/blue to you due to your perception of color and any combination of the beforementiioned factors. Do your research and as stated previously, 4100k - 5000k should provide you with the range of purest white and best light output.

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