ilso ER Firming Serum (Retinol) 30ml
Retinol sits eighteenth on this 30 ml ilso serum, behind niacinamide seventh, panthenol eighth and ectoin eleventh, with squalane, cholesterol and a hyaluronate stack under it. An evening step. Korean-market formula.
No reviews yet- Ships from our California warehouse
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- Suited to
- Dry skinCompromised barrierDehydrated skinSkin that has lost bounce
- Helps with
- Shoppers looking for Retinol in a serumRoutines that want Retinol and Niacinamide in one stepFilling the serum step with a Korean-market formulaAnyone who wants the Retinol serum sold on Korean shelves
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
Key benefits
- Retinol, the active this serum is built around
- Niacinamide, Allantoin, Dipotassium Glycyrrhizate and Adenosine on the same list, actives
- Tocopheryl Acetate and Pentaerythrityl Tetra-di-t-butyl Hydroxyhydrocinnamate further down the same list
- Tris(Tetramethylhydroxypiperidinol) Citrate and Tocopherol further down the same list
- Retinol named eighteenth on the manufacturer list printed on this page
- Sourced for the Korean market, not a US-shelf reformulation of this serum
Key actives
Retinolactive
Retinol is the alcohol form of vitamin A and the strongest retinoid available without a prescription. Skin converts it in two steps to retinoic acid, and it is used at night, at low percentages, for the look of fine lines and rough texture. The name on the box points at it, and it is named eighteenth on this serum's own ingredient list.
Niacinamideactive
Niacinamide is vitamin B3, and it is the most studied active in Korean formulation. The panel names it seventh on this serum's list, beside Retinol.
Allantoinactive
Allantoin is a comfrey-derived compound used to condition skin and soften the outer layer so it feels smoother. It is one of the standard additions to a formula built for easily irritated skin. The panel names it twenty-third on this serum's list, beside Retinol.
Dipotassium Glycyrrhizateactive
Dipotassium Glycyrrhizate is a water-soluble salt derived from licorice root. It is named twenty-fourth on this serum's list, alongside Retinol.
Adenosineactive
Adenosine is a nucleoside that Korea's own cosmetic authority recognises as a wrinkle-care functional ingredient, which is why it appears on so many Korean lists at a low level. It is used for the look of fine lines and is stable and well tolerated. The panel names it twenty-sixth on this serum's list, beside Retinol.
How to use
- Apply after toner and before moisturizer. Pat or smooth it over a cleansed face and let it absorb before the next step, AM and PM.
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 the Retinol and not three changes at once.
Is this the Korean-market serum or a US version?
The Korean-market one, Retinol and all. 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.
What else is on the list besides Retinol?
Niacinamide, Allantoin and Dipotassium Glycyrrhizate. The order they are printed in on this serum's panel is the order on the box, so you can see where Retinol sits relative to them. Further down the same panel: Adenosine, Tocopheryl Acetate and Pentaerythrityl Tetra-di-t-butyl Hydroxyhydrocinnamate.
- 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 it works
The ER Firming Serum (Retinol) is a 30ml serum, used after toner and before moisturizer, morning and evening. The active it is built around is Retinol, named eighteenth on its own ingredient list. The same list carries Niacinamide, Allantoin and Dipotassium Glycyrrhizate, so the active is not the only thing on it worth naming. How much of the Retinol stays on the skin, and for how long, is decided by the serum format rather than by the list alone. This is the Original Korean Formula, the serum ilso sells in Korea, Retinol and all.
Worth knowing
- Patch test this serum on a small area and wait a day before using it more widely, especially with Retinol on the list.
- Retinol is on this list, so keep this serum to the evening and build the nights up slowly rather than starting nightly.
Reviews
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Korean-market original
The Original Korean Formula serum from ilso, 30ml formulated with Retinol and Niacinamide, 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 the key actives in this formula, quoted from the medical sources linked beside each.
Vitamin A has a molecular structure that's tiny enough to get into the lower layers of your skin, where it finds and boosts collagen and elastin, which is a protein that strengthens your skin's flexibility.
Wilma Bergfeld, MDDermatologist, Cleveland Clinic It contains liquiritin, an active compound that helps to disperse and remove existing melanin in the skin.
Jennifer Chwalek, MDDermatologist, Byrdie
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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