K-Secret Seoul 1988 Retinal Serum Duo
K-Secret Seoul 1988 Retinal Serum Duo is a 30ml serum from K-Secret, used after toner and before moisturizer, morning and evening.
No reviews yet- Ships from our California warehouse
- Duties prepaid
- Suited to
- NormalCombinationDry
- Helps with
- A serum step in a Korean-style routineShoppers who want K-Secret's Korean-market formula rather than a US-reformulated versionEveryday use alongside the rest of a routine
In stock. Ships from our California warehouse, dispatched within 2 business days
You’re $100.00 away from free US shipping.
- Duties prepaid
- 30-day returns
- Free US shipping on orders of $100 or more
- Dispatched within 2 business days
How it works
K-Secret Seoul 1988 Retinal Serum Duo is a serum sold in K-Secret's Korean-market packaging and format. It takes the step after toner and before moisturizer of a Korean-style layering routine, used after toner, am and/or pm.
Key benefits
- What it is: a 30ml serum from K-Secret, for the serum step.
- Format: a serum used AM and PM, after essence and before moisturizer.
- Fits into the routine: delivers a targeted dose of its lead ingredients to the areas that need it most.
- Original Korean Formula: the version sold on Korean shelves, not a US reformulation.
How to use
- Use the Seoul 1988 Retinal Serum Duo after toner and before moisturizer, in the evening.
- As part of your nighttime skincare routine, apply a pea-sized amount to your skin after cleansing and toning. Gently massage until fully absorbed, then follow with a moisturizer.
- Toner first so the surface is damp, then this, then about a minute before your moisturizer goes over the top.
- Twice a day, every day. Do not stack it with a second serum of the same kind; two hydrating serums in one routine do the work of one.
Where does this serum go in my routine?
After toner and before moisturizer, morning and evening. Anything thinner than a serum goes on before it, and anything richer goes on after. If you are adding it to a routine you already like, give it a week on its own first, so what you see is it and not three changes at once.
Is this the Korean-market serum or a US version?
The Korean-market one. We match this serum to its Korean barcode before it reaches the shelf, which is the check that tells you which market release you are holding.
- 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
Worth knowing
- Patch test on the inner arm 24 hours before adding this to your face or scalp, as with any new product.
Reviews
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Korean-market original
The Original Korean Formula 30ml serum from K-Secret, held in the United States and shipped domestically.
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 skin care, quoted from the medical sources linked beside each.
Your skin barrier is basically your outer layer of the skin.
Melissa Piliang, MDDermatologist, Cleveland Clinic Pretty much every step of a Korean skin care routine is going to have some component of hydration.
Alok Vij, MDDermatologist, Cleveland Clinic
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