The reason for the slight difference is because when Remy human hair color is created, the hair must be bleached to achieve the desired color. After the hair has been dyed, it goes through a washing process - like you would dye your very own hair. On the contrary, when creating our high quality synthetic hair, we already use colored fibers which tend to be more saturated and different in color.  These are also two totally different materials, one is 100% real remy human hair and the other one is high quality synthetic fibers.