This incredibly powerful serum is a more intensive version of the original Y Theorem Serum. The formula melts effortlessly into skin while the black diamond particles aid deeper delivery of active ingredients. This serum helps to improve firmness and elasticity by encouraging collagen and elastin production in the skin. The serum is a powerful solution for hyperpigmentation, discolouration and uneven skin tone. Hydrate, volumise, smooth, brighten, and even the complexion with this intensive serum.