One Thing Green Tea Serum 80ml
Green Tea Serum is One Thing's ampoule serum (80ml), in the ONE THING, built around Camellia Sinensis Leaf Extract and Trehalose. It is used after toner and before moisturizer, as the routine's concentrated treatment step. This is the same formula Korean shoppers buy off the shelf in Seoul, not a version built for US retail.
No reviews yet- Ships from our California warehouse
- Duties prepaid
- Suited to
- NormalCombinationDrySensitive
- Helps with
- Dehydration and a barrier that feels compromisedReactive, easily irritated skin that needs calmingThe look of fine lines and a loss of firmnessA concentrated treatment step
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
- Camellia Sinensis Leaf Extract is named directly on Green Tea Serum's own ingredient list
- Trehalose is named directly on Green Tea Serum's own ingredient list
- Sodium Hyaluronate is named directly on Green Tea Serum's own ingredient list
- Green Tea Serum fits after toner and before moisturizer, as the routine's concentrated treatment step
- One Thing's Green Tea Serum is sold here as the Korean-market formula: over-labeled in English for US sale rather than reformulated for the US market
- Green Tea Serum keeps the Korean barcode and batch code that print on the unit sold on shelves in Korea
Key actives
Camellia Sinensis Leaf Extract
green tea extract, an antioxidant-rich polyphenol source. It sits at position 9 of 30 on this label's own ingredient list. This is read from the manufacturer's own listed order rather than assumed from the product name, which is what separates a genuine formula component from a name-only claim.
Trehalose
a sugar-derived humectant used to help a formula hold moisture. It sits at position 10 of 30 on this label's own ingredient list. This is read from the manufacturer's own listed order rather than assumed from the product name, which is what separates a genuine formula component from a name-only claim.
Sodium Hyaluronate
the salt form of hyaluronic acid, a humectant that holds water at the skin's surface. It sits at position 12 of 30 on this label's own ingredient list. This is read from the manufacturer's own listed order rather than assumed from the product name, which is what separates a genuine formula component from a name-only claim.
Allantoin
a soothing agent used to calm and condition sensitive skin. It sits at position 15 of 30 on this label's own ingredient list. This is read from the manufacturer's own listed order rather than assumed from the product name, which is what separates a genuine formula component from a name-only claim.
Adenosine
the ingredient Korea's own functional cosmetics notification system recognizes specifically for a firmer looking appearance. It sits at position 18 of 30 on this label's own ingredient list. This is read from the manufacturer's own listed order rather than assumed from the product name, which is what separates a genuine formula component from a name-only claim.
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.
What is Green Tea Serum?
It is One Thing's ampoule serum (80ml). Its own ingredient list names Camellia Sinensis Leaf Extract, Trehalose, Sodium Hyaluronate, Allantoin, positioned the way the key-actives panel on this page describes, rather than actives assumed from the product name. It is used after toner and before moisturizer, as the routine's concentrated treatment step.
How do I use Green Tea Serum?
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. Keep the same order every time you use it so you can tell what is actually working, and give a new step a few weeks before judging the result.
Is Green Tea Serum the authentic Korean-market formula?
Yes. This listing is One Thing's Korean-market formula: the same ingredient list, barcode and batch code as the unit sold on shelves in Korea, rather than a version reformulated for US retail. That is the whole reason to buy a Korean-market brand from a specialist rather than a general retailer.
Where does Green Tea Serum fit if I already use sunscreen or makeup?
Apply Green Tea Serum before sunscreen or makeup, and let it absorb fully first so it does not pill under the next layer. Sunscreen still goes on last in the morning, and makeup after that, regardless of how many treatment steps come before it.
Who is Green Tea Serum suited for?
It suits normal, combination, dry or dehydrated and sensitive skin, and it is not restricted to any one skin tone or age group. As with any new step, patch-test on the inner arm first if you are new to this formula or to One Thing.
- 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 it works
Green Tea Serum is an ampoule serum from One Thing. One Thing is a Korean single-ingredient skincare brand: each toner and serum is built from one named plant extract, with no added fragrance or color. On this jar's own ingredient list, Camellia Sinensis Leaf Extract, Trehalose, Sodium Hyaluronate, Allantoin, Adenosine are named directly, which is what the key-actives panel on this page is built from rather than from the product name alone. Camellia Sinensis Leaf Extract is green tea extract, an antioxidant-rich polyphenol source, and it is why this ampoule serum is positioned the way it is. Use it after toner and before moisturizer, as the routine's concentrated treatment step, giving it a minute to settle before the next layer goes on. One Thing sells this as the Korean-market formula, the same one stocked on shelves in Korea rather than a version built for the US market.
Worth knowing
- New to this formula or to the brand: patch-test on the inner arm and wait a day before applying it to the face.
- Discontinue use and rinse the area with water if redness, itching or irritation develops.
Reviews
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Korean-market original
Green Tea Serum, 80ml, ONE THING, One Thing's ampoule serum with Camellia Sinensis Leaf Extract and Trehalose.
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 Allantoin can tone down the dryness of the individual cells. It increases the water content of the skin, which means it helps to hydrate and moisturize.
Wilma Bergfeld, MDDermatologist, Cleveland Clinic
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