# K-Secret Seoul 1988 Retinal Serum Duo

The Original Korean Formula 30ml serum from K-Secret, shipped from California or direct from Korea.

- Brand: K-Secret
- Product: Seoul 1988 Retinal Serum Duo
- Price: $18.82
- Availability: In stock
- Size: 30 ml
- Market: Korean market, the version sold in Korea
- Made in: Republic of Korea
- EAN (barcode): 8809695240683
- Category: Serums & Ampoules

## 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 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.

## How to use

1. Use the Seoul 1988 Retinal Serum Duo after toner and before moisturizer, in the evening.
2. 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.
3. Toner first so the surface is damp, then this, then about a minute before your moisturizer goes over the top.
4. 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.

## FAQ

### 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.

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Page: https://korean-pharmacy.com/products/k-secret-seoul-1988-retinal-serum-duo