Yves Saint Laurent presents a revolution in foundation with Youth Liberator Serum Foundation: Medium to Full Coverage, Firming, 24 Hour Hydration SPF 20. This anti-aging foundation is infused with our award winning serum, Forever Youth Liberator Serum.Forever Youth Liberator Serum. Youth Liberator Serum Foundation combines 24 hours of non-stop hydrating properties to smooth and nourish the skin with our patented Color Tune-Up Complex to correct dullness giving you a newer, brighter complexion. From fair to dark complexions, Youth Liberator Serum Foundation corrects, unifies and evens all skin tones, giving the skin an instantly younger appearance. Available in 10 universal shades. SPF 20 broad spectrum UVA/UVB protection. 1 oz.