The YSL 'Vernis À Lèvres Amplifier' is an innovative new product designed to work as a lip color amplifier.
When applied to bare lips, these lip primers will add staying-power and change the undertone of any lip color you apply over top of them. Essentially, these work with the same principles of color theory. Most conventional lip colors have some kind of red tone, but they will also have blue or yellow or magenta undertones depending on the shade.
If you apply an opaque primary color underneath, these products will appear to shift the tone of that shade to the primer color. Consumers seeking versatility will enjoy playing around with these colored primers. Alternatively, the lip color amplifiers could be used alone for a super bold and playful look.