COSRX
The 6 Peptide Skin Booster Serum
COSRX's six-peptide booster serum, layering niacinamide with copper tripeptide-1 and sh-Polypeptide-121, worn after toner and before moisturizer, morning and evening.
No reviews yet- Ships from our California warehouse
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- Suited to
- MatureFine linesSensitiveCompromised barrier
- Helps with
- Fine lines and loss of bounceBarrier weaknessDehydrationEarly environmental damage
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- 30-day returns
- Free US shipping on orders of $100 or more
- Dispatched within 2 business days
How it works
A booster serum is something you add to a routine that already works, and the name here is the idea: peptides, in a light water-based fluid. It goes on after toner and before moisturizer, morning and evening, pressed in with flat palms on damp skin. Skin that looks tired and flat by the evening is the case it fits, and peptide work is cumulative rather than overnight. It layers under anything else already in the routine, which is what a booster is for. Twice a day, every day, on the neck as well as the face.
Key benefits
- Six named peptides run back to back at entries seven through twelve, exactly matching the count in the product name
- Niacinamide leads directly into the peptide stack at entry six
- Allantoin and sodium hyaluronate cushion the peptide stack immediately behind it
- Lightweight, fast-absorbing texture built to layer, not to replace a heavier step
- COSRX runs its own brand-portal verification: enter the batch number and expiry from your unit on cosrx.com
- Sourced for the Korean market, Korean barcode 8809598455658 intact on the box
Key actives
Acetyl Hexapeptide-8
leads six peptide ingredients on the list
Oligopeptide-68
another of the six peptide ingredients on the list
Niacinamide
supports a clearer, more even look
Sodium Hyaluronate
a humectant for the hydrating base
COSRX The 6 Peptide Skin Booster Serum
What are the six peptides in this booster serum and where do they sit on the list?
Six named peptides run back to back at entries seven through twelve: acetyl hexapeptide-8, copper tripeptide-1, sh-polypeptide-121, dipeptide diaminobutyroyl benzylamide diacetate, oligopeptide-68 and palmitoyl tripeptide-8. Niacinamide leads directly into that run at entry six, and adenosine appears further down the list as an additional actives layer. The count in the product's name matches the count of distinct peptide ingredients actually on the label.
Is a peptide serum like this suitable for sensitive or first-time peptide users?
The ingredient list contains no fragrance, essential oil, silicone, paraben, sulfate surfactant, mineral oil or added colourant, which is a relatively low-irritation profile for a first peptide product. Allantoin and sodium hyaluronate sit near the peptide stack for comfort and hydration, and a wide amino acid set rounds out the formula. Peptides themselves are not typically irritating, but as with any new step, introducing it gradually is the safer approach.
How long does it take to see a difference from a peptide serum?
Peptides work by supporting skin's ongoing processes rather than producing an immediate visible change, so the honest expectation is weeks of consistent use before firmness or texture reads differently. Niacinamide, positioned just ahead of the peptide stack, tends to show its evening effect on a similar timeline. Using the serum inconsistently will simply slow that timeline rather than causing harm.
Can this peptide serum be layered under a retinoid or brightening product?
This serum's list is built from peptides, amino acids and humectants, with nothing that would inherently conflict with a separate retinoid or brightening step used elsewhere. A common approach is to apply this serum first on clean skin, let it settle, then follow with a treatment product and moisturizer. Confirm the exact order against whatever other product's own instructions you are using.
How do I know my bottle is the genuine Korean-market version of this serum?
The barcode on this unit, 8809598455658, is the original Korean-market code, kept intact rather than covered by a domestic sticker. COSRX verifies units through its own system: locate the batch-check page on cosrx.com and enter the batch number and expiration date exactly as printed on your box, since reading those numbers directly off your own unit rather than trusting a seller's claim is the whole point of that check.
- 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
We accept
How to use
- Use the 6 Peptide Skin Booster Serum after toner and before moisturizer, morning and evening.
- Three or four drops for the face and neck, pressed in with flat palms rather than rubbed around.
- Toner first, this second, then moisturizer over the top, and sunscreen last in the morning.
- Twice a day, every day. Do not swap it in for your moisturizer; a booster is a layer under one rather than a replacement for it.
Reviews
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COSRX, Korean-market original
6 Peptide skin booster serum, 150 ml, with Niacinamide.
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.
COSRX verifies units itself. Find the verification page on cosrx.com and enter the batch number and expiration date printed on your unit. Read them off the package rather than from us, which is the point.
Source: COSRX FAQ
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.
Peptides can be anti-inflammatory, and chronic inflammation damages the tissue in your skin.
Wilma Bergfeld, MDDermatologist, Cleveland Clinic In skin, different peptides can encourage different things, from collagen formation to a reduction in inflammation to helping with wound healing depending on their structure.
Whitney Hovenic, MDDouble board-certified dermatologist and Mohs surgeon, Women's Health
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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