Semi-permanent and permanent colour both utilise oxidative dyes and peroxide to develop the colour. These kits contain two bottles that you mix together to get your colour. The colour they develop is very intense and developed to last 6–8 weeks. Permanent hair colour will also lighten your natural hair colour if desired. John Frieda® Colour Refreshing Gloss Cool Brunette is made with mild cosmetic dyes, which are found in many beauty products. This brunette hair gloss is designed just to add a hint of colour and shine to refresh hair colour. It will not lighten hair colour.