Actually you can dye your synthetic hair extensions if they are made of human hair but I do not recommend. Because the hair products have been dyed in the factory with special technology, the hair will be easily fragile if you color the hair again. If you would like to dye them anyway, please color them darker rather than lighter only, because bleaching hair extensions that have already been processed are extremely harmful for the hair. Therefore, I never recommend bleaching the hair, since the hair is not virgin human hair.
If you are coloring them, I recommend going to a hairdresser to color them for you, unless you are confident with your own ability to dye them. Always test synthetic hair extensions dye on a small weft before coloring the whole set.
I like to look at the synthetic hair extensions carefully. if the extensions appear to be all solid color and the hair all the same texture usually I assume they are synthetic. Upon looking at extensions that are marked human I check the hair for minor differences. Like a bit of a different texture and often you may find a gray one or two.
If you do buy synthetic hair extensions as soon as you get them home I would clip a tiny piece off. I didn’t burn a piece of the hair synthetic hair extensions curl up and smell like plastic when burned. Human hair extensions and Yaki turn to ash when burned and smell like burning hair. To test this take some hair out of your brushes or combs, burn it and compare the smell.
These is no quality standard for synthetic hair extensions right now. Good human hair extension should be smooth with thickness. When you check carefully in the light, will it with split ends? This proves if raw material are strictly controlled.