Editor's TipEditor's Tip

For best results, condition with Number 4™ Lumiere d’hiver Reconstructing Masque.

Number 4 Hair Care

Birchbox Breakdown

There was a time when we were a bit skeptical about hair oils—the last thing we wanted was a greasy, weighed down ’do. These days, however, we can't imagine a haircare routine without it. This strand-saving elixir gives drab, dull hair a coveted movie star shine (plus a whole host of reparative benefits). Our oil-free days are officially over.

How to Use

Distribute one to two pumps through damp hair, then style as usual. For added radiance, apply one pump of product to dry hair.

Cyclopentasiloxane,C13-14 Isoparaffin,Dimethicone,Dimethiconol,Phenyl Trimethicone,Perfluorononyl Dimethicone,Fragrance (Parfum),Benzyl Salicylate,Butylphenyl Methylpropional,Linalool,Hydroxyisohexyl 3- Cyclohexene Carboxaldehyde,Ethylhexyl Methoxycinnamate,Argania Spinosa Kernel Oil,Helianthus Annuus (Sunflower) Seed Oil,Glycerin,Sodium Ascorbyl Phosphate,Hydrolyzed Soy Protein,Macrocystis Pyrifera Extract,Ribes Grossularia Fruit Extract,Ribes Nigrum (Black Currant) Leaf Extract,Arctium Lappa Root Extract,Avena Sativa (Oat) Kernel Extract,Camellia Sinensis Leaf Extract,Chondrus Crispus (Carrageenan) Extract,Cymbopogon Schoenanthus Extract,Euterpe Oleracea Fruit Extract,Garcinia Mangostana Peel Extract,Hibiscus Sabdariffa Flower Extract,Hydrastis Canadensis (Golden Seal) Root Extract,Ilex Paraguariensis Leaf Extract

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Most Helpful Customer Reviews

Be careful
Sampled

Use very sparingly and in small amounts or else your hair will look very greasy

4
Was this review helpful to you? Yes | No 34 of 34 found this review helpful. Was this review helpful to you? Yes | No
Weightless Shine

Love it! I have very very fine, long, color treated hair, so I need a little extra strength/moisture and shine without weighing down my hair any more than usual. I've tried all sorts of serums and glossing creams and stuff in the past with usually average results at best - either I'm not getting the shine results I want or I look like a wet dog, all weighed down with goop. Bought a bottle of this on a whim since I've been such a fan of the other Number 4 products I've sampled, and I'm SO glad I did. This is it.

After a couple of uses, hair is exceptionally shiny and looks healthier than usual. However, my hair is NOT weighed down at all. If anything, it's moving more than usual. And it feels super soft. I'm hoping continued use does improve the health of my hair, but even if not I'd keep using this stuff based on looks alone.

5
Was this review helpful to you? Yes | No 40 of 42 found this review helpful. Was this review helpful to you? Yes | No
Love it!!!
Sampled

I usually use a lot of product, to keep my hair under wraps, but this stuff made me feel free and kept my hair soft and manageable!

5
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Looove love love
SampledPurchased

Love the silky smoothness & how i see results after a few uses. I got a sample, ended up buying it a week or so later

5
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restore and repair hair
Sampled

oh my gosh absolutely love love this stuff gives a great smooth shine to the hair definitely would buy this product

5
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Perfect for color treated hair
Sampled

I bleach my dark brown hair and this product keeps my ends moisturized and frizz free. I use a little extra before bed once a week for an added conditioning treatment. Doesn't leave my fine hair greasy at all.

5
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Really good
Sampled

I use this product when my hair is wet, it works really good...it gives my hair the shine I needed and makes it feel soft.

4
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This is the BEST product for my hair!
Sampled

My mother had a similar product when I was growing up, and I would always sneak into her room to use it, but now I have my own!!!

5
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Use it everyday!
Sampled

I LOVE this hair oil! A little bit goes a long way. I use it on damp hair before I dry/style and sometimes I'll use it afterward for a little extra shine - either way, it never makes my hair oily. Will definitely consider buying more of this product.

5
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Good for Thick Coarse Hair
Sampled

My hair is really thick and coarse, so it's hard to find a product that makes my hair smooth and tame. I was really surprised how great a few drops on my wet hair transformed my thick poofy hair into smooth and lightweight once blown dry. I also like to use a small dab on the ends of my hair after its dry.

4
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