GUILT-FREE GLAMOUR!® Cobra is a light cocoa brown hair dye with chestnut undertones! For best results use on pre-lightened hair! Cobra has a warm undertone so it should work well on natural blonde hair but always make sure to strand test to see if it will work on your hair level! If you’d like to punch up this brown to make sure it will cover your base tone, try adding in a few drops of Raven or Blue Panther to your mix! All semipermanent hair dyes work best on pre-lightened hair! Always do a strand test to see if it will work well on your hair level.