Amika Bust Your Brass mask is a toning and strengthening repair mask. This ultra-luxe toning treatment is clinically proven to strengthen + hydrate damaged hair and help bring blonde, silver + gray back to life. Who it's for all blondes, silver and grays looking to cool warm tones why it's special Bring blonde back to life. packed with bond fortifying technology, plant butters, vegan protein, and ultra-violet pigments-- for your strongest + brightest mane yet! the proof is in our claims - bust your brass toning + strength mask is clinically proven to significantly brighten, hydrate + strengthen, resulting in hair that is 8x more conditioned, 2.2x stronger + with 56% less breakage.* safe for strands: clinically proven to be safe for color-treated hair.** ultra-hydration - this luxurious mask is packed with 3 different types of plant butters and adds a healthy dose of moisture to dry strands. tones brassiness - counteract any yellow, unwanted brassy hues for an icy blonde, silver or gray. strengthens + reduces breakage while also helping to prevent future damage.