Courtney’s revolutionary acidic serums are functional in various ways for different skin conditions and concerns. Enjoy the FULL collection of all five Molecules – to gain the benefits of glycolic acid, lactic acid, kojic acid, arbutin, salicylic acid, and more! HINT: Apply the thinner products (the Resurgence Molecules and Purifying Molecules) on a cotton round and apply over your skin morning and night. Alternating these is key! You may then apply the Brightening Molecules, Plumping Molecules, and Illuminizing Molecules interchangeably for serious results!