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Editor's Tip

Before applying this leave-in serum, wash your hair with Kérastase’s shine-boosting Cristalliste shampoo and conditioner.

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Kérastase

4.0 out of 5 stars, based on 309 reviews 309 Reviews / Write a Review
$42.00 includes Free Shipping
Size: 50ml   

Availability: In stock

$42.00

Birchbox Breakdown

Ever since we watched the first season of “Gossip Girl,” we’ve been huge fans of Blake Lively’s flowing waves. So we were excited to learn that the blonde actress was the inspiration behind Kérastase’s new serum. Specially designed for long hair, the leave-in treatment adds a high-definition shine while sealing each cuticle (bye bye, split ends). Plus, the light, gorgeously scented formula won’t weigh down your strands.

How it Works

This luxe serum is made with sophisticated light reflectors to add mega-gloss and shine while smoothing away frizz. A generous amount of aloe vera—high in natural amino acids and vitamins—softens and restores dry, brittle ends (the number one problem for girls with long locks).

How to Use

Smooth a quarter-size amount through damp or dry hair, avoiding the roots and concentrating on your lengths and ends.

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Product Reviews & Sample Feedback

4.0 out of 5 stars, based on 309 reviews 309 Reviews
4.0 out of 5 stars
Show details
5 Star
128
4 Star
89
3 Star
60
2 Star
25
1 Star
7
Write a Review
5 out of 5 stars
Love it!

This is such an awesome product! It smells fantastic and makes my hair shiny and manageable! A little bit goes a loooong way however, so use sparingly.

4 out of 5 stars
Awesome

I love how this product does not make my long hair look stringy or greasy. I like to use it every day.

5 out of 5 stars
light weight, absorbs fast

Looking for a while for a hair serum that is light weight, smells great, and absorbs fast. this serum does not weigh my hair down and i love it!

5 out of 5 stars
Great hair serum!

I love the smell of this serum, I also love that it's light weight. It leaves your hair shiny and very healthy looking. I highly recommend this product.

5 out of 5 stars
Can't wait to have long hair again.

Used the sample while I was still growing out my hair to donate. The only glossing product I've used that hasn't weighed my hair down. It was glorious and helped control flyaways. As my hair continues to grow out again, I will be buying this complete line of hair care products. The shine, the body, enhancing my natural waves... with 17 inches of hair it takes a miracle product. this is that product.

4 out of 5 stars
Super Gloss

With long blonde hair, this is the perfect product to finish off your style. A little goes a long way so the bottle lasts for months and months.

5 out of 5 stars
Liquid magic.

I have searched high and low for a substitute and it does not exist. Feels like water in your hands and silk in your hair. I'm convinced I have been able to grow out my hair only by the help of this product!

4 out of 5 stars
Great Repair Product

I live a pretty active lifestlye and all the different settings can be hard on my hair. But I have noticed a tremendous difference in my locks if I apply this after showering. It certainly doesn't prevent the split ends from happening, but your hair is so glossy and smooth that it minimizes their appearance and eliminates their feel.

4 out of 5 stars
!

i love serums for my dry hair. this made my hair feel and look silky smooth. you should try it out!

5 out of 5 stars
I love this stuff!

I have long hair -- middle of my back -- and this is definitely the best hair serum/smoother I have ever used. It's not sticky or heavy, just goes on weightless and leaves my hair looking and feeling healthy and touchable. I highly recommend it!