numbuzin No.5+ Vitamin Concentrated Serum 30ml
Numbuzin No.5+ Vitamin Concentrated Serum 30ml carries three separate vitamin c forms on its own ingredient panel, including 3-0-Ethyl Ascorbic Acid, Ascorbic Acid, Ascorbyl Glucoside.
No reviews yet- Ships from our California warehouse
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- Suited to
- normalcombinationdryoily
- Helps with
- tone and texture supported by Niacinamidedaily 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
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How it works
The panel on this serum names three forms of vitamin c rather than one: 3-0-Ethyl Ascorbic Acid, Ascorbic Acid, Ascorbyl Glucoside. 3-O-Ethyl Ascorbic Acid is a stable vitamin C derivative that skin converts to ascorbic acid. It survives in a formula far better than pure vitamin C and works at a gentler pH, so it suits skin that finds the pure acid uncomfortable. On this panel it sits alongside Vaccinium Vitis-Idaea Fruit Extract, Niacinamide and Tranexamic Acid. Lingonberry fruit extract, a Nordic berry. It carries anthocyanins, arbutin and fruit acids, and it is used as an antioxidant botanical.
Key benefits
- Three forms of vitamin c on one panel, not a single token inclusion
- Vaccinium Vitis-Idaea Fruit Extract on the same panel, the formula's plant extract
- Niacinamide on the same panel, the formula's active
- 30 ml to a unit
- Korean GS1 barcode matched against a Korea sourcing supplier's record for this item
Key actives
3-0-Ethyl Ascorbic Acid
3-O-Ethyl Ascorbic Acid is a stable vitamin C derivative that skin converts to ascorbic acid. It survives in a formula far better than pure vitamin C and works at a gentler pH, so it suits skin that finds the pure acid uncomfortable.
Ascorbic Acid
Ascorbic Acid is pure vitamin C, the most researched form and also the least stable: it needs a low pH and airtight packaging to stay active. It is an antioxidant used for the look of dullness and uneven tone.
Ascorbyl Glucoside
Ascorbyl Glucoside is vitamin C bound to glucose, which keeps it stable until enzymes in skin release it. It is a mild, slow-release route to a vitamin C formula.
Vaccinium Vitis-Idaea Fruit Extract
Lingonberry fruit extract, a Nordic berry. It carries anthocyanins, arbutin and fruit acids, and it is used as an antioxidant botanical.
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.
Tranexamic Acid
Tranexamic Acid is a synthetic amino acid derivative used for the look of stubborn discolouration and post-blemish marks. It is water soluble, stable and comfortable next to niacinamide, which is how it is usually paired.
How do I know this is authentic and not a US-reformulated version?
Check the box against the listing: an authentic Korean-market SKU carries Korean-primary packaging and an intact Korean-market batch code, not a US-only relabel. Numbuzin's Korean-market formulas are sourced specifically to preserve that, rather than substituted for the US-shelf version some retailers carry under the same name.
When in a routine should I use this serum?
Use it as the serum step, AM and PM, after toner and before moisturizer. Placing a serum out of order is the most common reason a Korean routine feels like it is not working, so keep this one at its own step rather than doubling it up with a product built for a different stage. Give it a few weeks at that placement before judging the result.
Is this the same formula sold in Korea, or a US version?
This is sourced for the Korean market rather than reformulated for US shelves. 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.
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.
What does Panthenol do in this formula?
Panthenol is pro-vitamin B5, a conditioning agent Korean formulas lean on to keep the surface feeling soft rather than tight. It has a long track record in Korean skincare as a mild, everyday conditioning agent that layers cleanly under the rest of a routine. 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
- Apply after the toner while the skin is still damp so a small dose covers the face in one pass.
- Press it over the whole face rather than onto the marks only, since even tone needs even coverage.
- Always follow with a cream, because a concentrated layer left unsealed is where tightness comes from.
- Do not skip the morning sunscreen, since tone work without that last layer is undone faster than it is built.
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 Niacinamide, 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.
Using topical vitamin C can result in less cell damage and better-looking skin.
Melissa Piliang, MDDermatologist, Cleveland Clinic Topical tranexamic acid 5% cream is under investigation in the treatment of melasma and is showing promising results in the treatment of epidermal-type melasma.
Faisal R AliConsultant Dermatologist, DermNet NZ
1 more professional perspective
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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