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
Really like it
Sampled

Tames my frizzy hair. Thinner consistency than what I am used to but still works. Doesn't really have a smell to it.

5
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Smoothe
Sampled

I'm wearing my hair short and natural gray these days; this added softness to the touch and shine to my hair and calmed down my thick hair.

4
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Smells great
Sampled

I received this in my monthly birchbox and although i only got a small sample it has lasted me a long time! It works great and it makes my hair smell wonderful! I 100% recommend!

4
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nice hair oil, not too heavy
Sampled

This hair oil is pretty great. it doesn't weigh down my fine hair. The scent is pretty neutral.

4
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Hydrsting
Sampled

I use this at night and my hair is soft and feels replenished when I wake up.. Use about once a week tip treat my hair!

5
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Repair oil
Sampled

You only need a small amount if this to have your hair feeling totally repaired. This sample size lasted a good amount of uses because of this . It had a great smell and didnt leave my hair feeling oily or heavy. Great product to repair hair that i treat with many thermal tools

4
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Makes for Shiny hair!
Sampled

I have fine but curly and frizzy hair. I tried it after I blow dried and flat ironed my hair. I put a tiny amount in my palm, rubbed my hands together and ran them down my hair, focusing on the ends . It made my hair shiny and soft and it has a nice smell. Be careful, I can see how overdoing it would make your hair look greasy.

4
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AMAZING.
Sampled

Let me start out with the scent of this product- it is intoxicating and I love it. My scalp gets very dry during the winter months and this soothes it on contact. I was surprised that upon applying it on dry hair it did not make my hair look oily at all but rather added volume and texture. I will definitely be purchasing this product.

5
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