Acid link to more firmly fix the keratin of Kerafect Connector. After applying the connector, apply the acid link and leave it for 3 minutes, then rinse. This saves time and further increases hair strength, allowing you to maximize the connector's effect by 120%. After that, applying CMC link and rinsing will replenish all the necessary nutrients for your hair. This allows you to perform an essential system treatment at home that surpasses salon treatment menus. (CMC link can also be used as an out-bath treatment depending on how you use it. It has an overwhelming cost performance, with 150g yielding a capacity of 3L or more.) We strive for smooth and pleasant transactions, so thank you for your cooperation!