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Free US shipping on orders of $100 or more. 100% authentic Korean-market formulas. Ships from California or direct from Korea, tracked to your door. Intact Korean batch codes on every unit.

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KOREAN PHARMACY

Isntree

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Hyper Vitamin C23 Serum 20ml

Isntree Hyper Vitamin C23 Serum is a 20ml serum with Ethyl Ascorbyl Ether, used after toner and before moisturizer, morning and evening.

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$35.00

20 ml

$17.50 per 10 ml

  • Korean-market formula
  • Ships from California or direct from Korea
  • Korean barcode and batch code intact
Suited to
Dehydrated skinSensitive skinDull, uneven tone
Helps with
Shoppers looking for Ethyl Ascorbyl Ether in a serumRoutines that want Ethyl Ascorbyl Ether and Adenosine in one stepFilling the serum step with a Korean-market formulaAnyone who wants the Ethyl Ascorbyl Ether serum sold on Korean shelves

Purchase options

In stock. Arrives in 3 to 7 business days

We accept

You’re $100.00 away from free US shipping.

  • 30-day returns
  • Free US shipping on orders of $100 or more
  • Tracked delivery to your door

How it works

The Hyper Vitamin C23 Serum is a 20ml serum, used after toner and before moisturizer, morning and evening. The vitamin it is built around is Ethyl Ascorbyl Ether, named eighth on its own ingredient list. The same list carries Adenosine, Ascorbic Acid and Tocopherol, so the vitamin is not the only thing on it worth naming. How much of the Ethyl Ascorbyl Ether 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 Isntree sells in Korea, Ethyl Ascorbyl Ether and all.

Key benefits

  • Ethyl Ascorbyl Ether, the vitamin this serum is built around
  • Adenosine on the same list, an active
  • Ascorbic Acid and Tocopherol on the same list, antioxidants
  • Gardenia Florida Fruit Extract on the same list, a plant extract
  • Polyglycerin-3 and Hydroxyethyl Urea further down the same list
  • Panthenol further down the same list

Inside the formula

Inside the formula

17
Ingredients declared
No fragrance
on the list

1 of 2

Isntree Hyper Vitamin C23 Serum 20ml

How to use

  1. Start with three drops every other morning and move to daily only once it feels comfortable.
  2. Apply after toner on skin that is barely damp, then wait a minute before the next layer.
  3. Always finish a morning routine that includes this with sunscreen as the last step.
  4. Do not layer it with an exfoliating acid in the same routine, since two sharp products at once is what causes stinging.

Worth knowing

  • Patch test this serum on a small area and wait a day before using it more widely, especially with Ethyl Ascorbyl Ether on the list.
  • Introduce this serum on its own for the first week, so anything your skin does is traceable to the Ethyl Ascorbyl Ether rather than to three changes at once.

Complete the routine

Total for 3 items$95.00

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Isntree Hyper Vitamin C23 Serum 20ml

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Isntree, Korean-market original

The Original Korean Formula serum from Isntree, 20ml formulated with Ethyl Ascorbyl Ether and Adenosine, shipped from California or direct from Korea.

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.

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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