numbuzin No.6 Deep Sleep Mask Serum 50ml
Numbuzin No.6 Deep Sleep Mask Serum 50ml carries four separate hyaluronic acid forms on its own ingredient panel, including Sodium Hyaluronate, Hydrolyzed Hyaluronic Acid, Hyaluronic Acid, Sodium Hyaluronate Crosspolymer.
No reviews yet- Ships from our California warehouse
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- Suited to
- normalcombinationdryoily
- Helps with
- tone and texture supported by Glycerindaily hydration through the serum stepa Korean-market formula rather than a US reformulationa routine step matched to this format
In stock. Ships from our California warehouse, dispatched within 2 business days
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- 30-day returns
- Free US shipping on orders of $100 or more
- Dispatched within 2 business days
How it works
The panel on this serum names four forms of hyaluronic acid rather than one: Sodium Hyaluronate, Hydrolyzed Hyaluronic Acid, Hyaluronic Acid, Sodium Hyaluronate Crosspolymer. Sodium Hyaluronate is the salt of hyaluronic acid, and it is what most products labelled hyaluronic actually contain. The salt dissolves more readily and the molecule is smaller, so it sits in the outer layer of skin rather than only on top of it. On this panel it sits alongside Glacial Water, Niacinamide and Chlorella Vulgaris Extract. Glacial Water is meltwater collected from glacier ice, used in place of ordinary water as a formula base. It is water with its own mineral profile rather than an active.
Key benefits
- Four forms of hyaluronic acid on one panel, not a single token inclusion
- Glacial Water on the same panel, the formula's plant extract
- Niacinamide on the same panel, the formula's active
- 50 ml to a unit
- Korean GS1 barcode matched against a Korea sourcing supplier's record for this item
Key actives
Sodium Hyaluronate
Sodium Hyaluronate is the salt of hyaluronic acid, and it is what most products labelled hyaluronic actually contain. The salt dissolves more readily and the molecule is smaller, so it sits in the outer layer of skin rather than only on top of it.
Hydrolyzed Hyaluronic Acid
Hydrolyzed Hyaluronic Acid is hyaluronic acid cut into much shorter fragments. The smaller the fragment, the further into the outer layer it can settle, which is why serums stack several sizes together instead of using one.
Hyaluronic Acid
Hyaluronic Acid is a sugar chain the body already makes, and one gram of it can hold several litres of water. In a formula it is a humectant that pulls water to the surface of skin and holds it in a film, which is what makes skin look plumper while it is there.
Sodium Hyaluronate Crosspolymer
Sodium Hyaluronate Crosspolymer is hyaluronic acid linked into a mesh. It holds water in a soft gel on the surface rather than sinking in, and it releases that water slowly through the day.
Glacial Water
Glacial Water is meltwater collected from glacier ice, used in place of ordinary water as a formula base. It is water with its own mineral profile rather than an active.
Niacinamide
Niacinamide is vitamin B3, and it is the most studied active in Korean formulation. It is used at roughly 2 to 5 percent for the look of uneven tone and visible pores, and it is water soluble, stable and comfortable beside almost every other active, which is why it turns up in so many lists.
Chlorella Vulgaris Extract
Chlorella Vulgaris is a freshwater green algae. Its extract carries proteins, chlorophyll and amino acids and is used as a conditioning ingredient.
Is this the same formula sold in Korea, or a US version?
This is the Original Korean Formula, carried through with its intact Korean-market batch coding. Numbuzin sells a separate reformulation on some US shelves, and this listing is not that version. The Korean-market batch coding and packaging travel with it, which is the detail worth checking against the box on arrival.
Where does this formula come from?
It comes from the Korean-market catalog rather than a US-shelf reformulation, and the packaging carries the same Korean-market batch coding a shopper would find on the box in Korea. That sourcing is checked on this row before the page is written, not assumed from the product name. It is the detail worth checking against the box on arrival.
Can I use this alongside other actives in my routine?
Yes. Glycerin is the lead active here, and it is formulated to sit alongside the rest of a routine rather than replace it. Introduce any new step on its own for the first week or two before adding it next to another strong active, so it is easy to tell which product is responsible for any change. Once it is settled into the routine, it layers the way any other serum in a Korean routine does.
What does Sodium Hyaluronate do in this formula?
Sodium Hyaluronate is the salt of hyaluronic acid, and it is what most products labelled hyaluronic actually contain. The salt dissolves more readily and the molecule is smaller, so it sits in the outer layer of skin rather than only on top of it. It is named on this product's own ingredient panel.
What does Niacinamide do in this formula?
Niacinamide supports an even-looking skin tone and works alongside the formula's humectants to keep the surface comfortable. It is one of the most studied actives in Korean formulation for tone evenness and is gentle enough for daily AM and PM use. It sits at its own position on this product's own ingredient list rather than being assumed from the product name.
- Ships from
- California
Duties are prepaid. Nothing is owed at delivery. Returns are accepted for 30 days, by mail.
Orders ship from our California warehouse, dispatched within 2 business days, and arrive in 3 to 5 days. Shipping is free on orders of $100 or more.
We split shipments free, so one out-of-stock item never holds up the rest of your order.
Where this unit came from
- 1Seoul
Bought as Korean-market stock - 2Customs
Duty paid by us before it enters the US - 3California
Ships domestically, no international leg
We stock the version of a formula that is sold in Korea, not the release a brand prepares for another market under the same name.
Every unit keeps its original barcode and batch code intact, so the unit in your hands can be checked against the brand’s own records.
Import duties are paid by us before the parcel reaches you, so nothing is owed at the door, and returns run for 30 days.
Every claim on this page traces to the unit in the box, the barcode, the batch code and the price you can read for yourself.
Payment and security
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How to use
- Finish the rest of your evening routine first, so this goes on over anything thinner.
- Press a thin even layer across the face and down the neck rather than rubbing it in.
- Leave it on overnight and cleanse as usual in the morning instead of adding more over the top.
- Do not use it as well as your night cream, since it stands in for that step rather than joining it.
Worth knowing
- Patch test on the inner arm first if trying a new brand's formula for the first time.
- Stop use and check the ingredient list against any known sensitivities before continuing.
Reviews
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Korean-market original
The Korean-market serum built around Glycerin, from Numbuzin, sourced for the Korean market and reviewed before it ever reaches this page.
Verify your unit when it arrives
Verify your unit when it arrives
Korean-market stock with the original barcode and batch code intact, exactly as it left Korea.
Match the batch code on the box against the code printed on the bottle or tube itself; the two are stamped separately and should agree.
On the unit itself
- The Korean-market barcode, unaltered from the retail package.
- The manufacturer’s batch code, exactly as the maker printed it.
정품Genuine article, Korean-market stock
What professionals say
What professionals say
What skin-care professionals say about the key actives in this formula, quoted from the medical sources linked beside each.
Hyaluronic acid helps bind water to collagen, which traps water in the skin. That helps make the skin more plump and full-looking.
Samantha Stein, PA-CDermatology physician assistant, Cleveland Clinic Niacinamide helps reduce the appearance of pores in a few ways. By strengthening the skin barrier and improving elasticity, pores appear less noticeable and more even.
Ashlyn YankeAesthetician, Cleveland Clinic
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