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custom hair mask

7.5oz - $19.99
  • An intensive weekly deep conditioning treatment that helps nourish and hydrate dry, damaged, or otherwise lackluster hair.
  • A customizable formula that delivers an optimal blend of nutrients to help give your hair the moisture it needs while also providing an added boost of your selected hair goals.
  • Formulated with a hair-healthy blend of Japanese sake extract, argan oil, jojoba ester oil, and a custom blend of natural ingredients depending on your hair goals.
  • Designed for in-shower use.
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All Function of Beauty products are formulated without sulfates, parabens, phthalates, or gluten, and are always certified vegan and cruelty-free.


recommended use

After shampooing and conditioning, coat your strands with the mask, ensuring an even application from the mid-shafts to the ends. Leave on for the recommended amount of time, then rinse. For the best results, use once or twice a week.


great for...

Hair mask is recommended for all hair types as it is specially formulated for your unique hair goals and needs. It is especially recommended for those with dry, damaged, or over-processed hair.

the people have spoken

The above testimonials were shared by customers who received a sample as part of our testing group.

got questions?

How is hair mask different than my regular conditioner?

While our in-shower conditioners are chock full of hydrating and conditioning ingredients, the custom hair mask is formulated with higher active levels of oils & conditioning agents. Allowing it to rest on the hair for extended periods of time will provide better cuticle penetration and help heal the cortex. This product is mainly intended for people with more dry, damaged hair, although it can be used by all hair types.

How can I tell if my hair is damaged?

While hair damage can mean a number of different things, the most common signs of it include hair that is dull, rough in texture, dry, extremely tangled, or showing signs of split ends and breakage.

What is the difference between hair mask and choosing a deep conditioning or hydrating goal?

The hair mask is formulated with higher levels of unique active ingredients such as argan oil, Japanese sake, and jojoba ester oil, as well as more conditioning agents than you’d get in our regular hydrate and deep condition hair goals. Allowing the product to rest on the hair for an extended amount of time will provide better cuticle penetration and help heal the cortex, which will ultimately help improve your overall hair health.

I have fine hair, is hair mask good for me?

Yes, like all of our products, the hair mask is 100% customized to work for your specific hair type. We do however recommend avoiding your scalp when applying the mask to ensure it doesn’t weigh your hair down.

Do you apply hair mask to your entire head?

We recommend applying the mask from the mid-shaft to the ends of your hair, combing through with a wide-toothed comb for even application. Be sure to also avoid the roots to help maintain volume!

Could I leave it in overnight?

No, we do not recommend leaving the mask on overnight.
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