Yellow Bottle 50% Straightening and 50% Constructor: The Yellow bottle provides all the values that the Black bottle adds to the hair. Additionally, it is a product for straightening curly hair. It is an ideal straightening and care product for medium curly hair. It has a permanent effect of 2 - 3 months. Note: Follow-on shampoos used at home must be salt-free products. Salt content reduces the longevity of the product. It is the number one choice of women who want to apply advanced keratin to their hair. It gathers and revitalizes the hair. It can be applied to all hair types. It is suitable for everyone, men and women, over the age of 14. Permanence period is between 4-6 weeks. Our gold keratin treatment, which has a gel structure, contains hydrolyzed keratin. It provides 50% straightness by replacing the keratin in the hair. Hair loses 25% of its keratin during lightening and dyeing processes, especially in platinum-blonde tones. With the application of our yellow bottle, this loss in hair is minimized. If pressed correctly with our renewed formula with gold glitter, the flatness rate can reach up to 70%. The raw materials of our formula are hyaluronic acid and aloevera extract. Our product absolutely does not contain formaldehyde. It is not recommended for use by people under 14 years of age and pregnant women.