Best $4 purchase I've ever made at Ulta!! I just used it and my skin looks and feels amazing. I love how simple and clean the process is.....cleanse face, open packet, unfold and apply cotton mask, leave on for 30 minutes, remove, press excess serum into skin and top off with moisturizer. Most of my redness and acne marks were instantly lightened and my skin feels super hydrated. I will definitely repurchase and will be looking for more K-Beauty products to try ASAP!