Cosme Decorte White Logic Chrono Genesis Brightening Concentrate (Whitening Serum) Normal Concentration x 3 packets 1.8X x 3 packets One backing card will be included. We have 3 more packets of each in stock, so additional quantities are available. According to the store clerk, For first-time users, redness may occur, so start with the normal concentration, and if there are no problems, then use 1.8X, starting with half a packet for the first use. If you have any questions, please feel free to ask.