The Chromatic Collection is a set of textures that gives an extra layer of customization to the hairstyles.
You can mix colours, add ombre gradients, highlights and tint the roots, and all of that while keeping the files small to save disk space.
Normal Hairstyles
Maxis Match Hairstyles
Fringes
Accessories
Scalp Textures
The Sims 2 Hairstyles
The Sims 3 Hairstyles
The Sims 4 Maxis Match Hairstyle