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custom leave-in treatment

8oz - $19.99
  • An ultra-lightweight conditioning cream that is meant to be left on your hair to help give it an extra boost of your selected hair goals.
  • Individually formulated to work for your unique hair type and goals.
  • Smooths, hydrates, and protects hair, giving it everything it needs to live its best life.
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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

Leave-in treatment can be applied post-shower to either wet or dry hair depending on your styling preference. It can be used on wash days, in between washes, or for quick touch-ups on-the-go. No rinsing necessary.


great for...

Leave-in treatment is recommended for all hair types as it is specially formulated to address your unique hair goals and needs.

the people have spoken

Stars4.8 / 5
33,172 reviews

got questions?

Will leave-in treatment make my hair oily?

No, the product is super lightweight and provides just an extra dose of soft conditioning that won’t weigh your hair down (plus it’s totally customized for your hair profile!). If you have fine or oily hair, we do recommend avoiding your scalp and starting with just half a pump to get your hair acclimated to the feel of the product before gradually adding in more until you achieve your desired results.

Will leave-in treatment help detangle my hair?

Definitely! It will also help smooth, hydrate and protect your hair in ways that in-shower products can’t, making it a necessary third step in your daily hair care routine.

When should I use leave-in treatment?

We recommend using leave-in treatment on damp hair before heat styling to help prevent damage. You can also use it on dry hair to help smooth out frizz and flyaways and provide an extra dose of shine and hydration.
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