Master Patch X-Large
An oversized hydrocolloid patch with niacinamide in the material, shaped to cover a whole zone rather than a single spot.
No reviews yet10ea
- Korean-market formula
- Ships from California or direct from Korea
- Korean barcode and batch code intact
- Suited to
- Uneven toneDullOilyCombination
- Helps with
- Uneven tone and dullnessExcess oilBarrier weakness
Sold out.
Tell us where to send it
One email, the moment this exact unit is back in stock. Not a newsletter and not a sequence, and your address comes off the list the second it is sent.
- 30-day returns
- Free US shipping on orders of $100 or more
- Tracked delivery to your door
How it works
One small patch cannot cover a cluster of congestion across a chin or a jawline, which is what the oversized cut is for. This is the extra-large patch in COSRX's Master Patch range, shaped to cover an area rather than a single point. It goes on last, on completely dry skin, and it holds best when everything under it is bare. The dressing takes up what the area gives off, and the parts of it that have been working turn cloudy. One patch per session, overnight, and it comes away best slowly from one edge.
How to use
- Press one Master Patch X-Large over the area at the end of the evening routine, on clean dry skin.
- Smooth it down from the middle of the patch outward so the whole edge lies flat against the skin.
- Nothing goes over it, and the skin under it needs to be bare and dry for it to hold.
- One patch per session, overnight. Do not peel it off quickly; lift one edge slowly so it does not take skin with it.
COSRX Master Patch X-Large
What is the Master Patch X-Large designed to do?
This is an oversized hydrocolloid patch built on cellulose gum, hydrogenated poly(C6-20 olefin) and polyisobutene, the absorbent adhesive base shared across the Master Patch line, with niacinamide named last on the six-entry list. The larger cut is meant to sit over a wider zone, such as a chin or forehead cluster, rather than one isolated spot. Ten patches ship per box, sized for covering rather than spot-by-spot use.
Is this patch okay for skin that reacts easily?
Fragrance, essential oil, denatured alcohol and silicone are all absent from the ingredient list, along with parabens, sulfate surfactants, mineral oil and added colourant. The material list runs to only six entries total, cellulose gum and the copolymer base doing the adhesive work with niacinamide the active ingredient named on it. A short list lowers the number of things that could cause a reaction, though any individual ingredient, niacinamide included, can still affect specific skin differently.
Does one patch clear a breakout overnight?
A hydrocolloid patch works by drawing fluid out of a spot into the dressing itself, which is why the center turns visibly white or cloudy as it fills. That absorption happens over hours, not the moment it's applied, and niacinamide sitting in the material is a slow, repeated-use ingredient rather than a one-application fix. Replacing the patch once it's saturated, rather than expecting a single overnight patch to finish the job, is the realistic way to use it.
Can I wear this under makeup or with other blemish products?
The patch itself has a skin-toned, matte finish that can sit under makeup once it's fully pressed down. Because nothing on this ingredient list overlaps with a leave-on treatment like a salicylic acid serum, applying that kind of product to clean skin before the patch, rather than on top of it, keeps the two from interfering with each other. Layering order matters more than layering amount here.
How can I confirm this is a genuine Korean-market COSRX patch?
The EAN 8809598454774 is the barcode printed on the real box, worth checking against your unit directly. Beyond that, COSRX runs its own verification: the batch number and expiration date on your box can be entered on the verification page at cosrx.com. Reading those two codes off your own packaging is the actual check, not anything printed in this listing.
Full INCI (6): Cellulose Gum, Hydrogenated Poly(C6-20 Olefin), Pentaerythrityl Tetra-di-t-butyl Hydroxyhydrocinnamate, Polyisobutene, Styrene/Isoprene Copolymer, Niacinamide
Ingredient list read from cosrx.com on 10 September 2026.
6 of 6 explained
- Cellulose Gum thickener
- Cellulose Gum is plant cellulose modified to dissolve in water. It thickens, holds particles in suspension and gives a smooth, slippery body.
- Hydrogenated Poly(C6-20 Olefin) emollient
- Hydrogenated Poly(C6-14 Olefin) is a synthetic hydrocarbon emollient. It gives a smooth, silicone-like glide and is completely stable, so it does not go rancid.
- Pentaerythrityl Tetra-di-t-butyl Hydroxyhydrocinnamate antioxidant
- This is a stabiliser that keeps the oils and fragrance in a formula from oxidising. Its job is the shelf life of the product rather than any effect on skin.
- Polyisobutene film former
- Polyisobutene is a synthetic polymer that forms a flexible, water-resistant film. It gives gloss and holds a formula in place, which is why it appears in lip products and long-wear textures.
- Styrene/Isoprene Copolymer film former
- Styrene/Isoprene Copolymer is a synthetic rubber used in patch adhesives. Its contribution is elasticity: the film stretches with skin instead of lifting at the edge.
- Niacinamide active
- Niacinamide is vitamin B3, and it is the most studied active in Korean formulation. It is used at roughly 2 to 5 percent for the look of uneven tone and visible pores, and it is water soluble, stable and comfortable beside almost every other active, which is why it turns up in so many lists.
- Market
- Korean market, the version sold in Korea
- EAN (barcode)
- 8809598454774
- Made in
- Republic of Korea
- Volume
- 10ea
- Category
- Hydrocolloid Acne Patch
- Actives
- Niacinamide
- Ships from
- California or Korea
Orders ship from California or direct from Korea with tracked delivery to your door, and both routes carry the same Korean-market release. Shipping is free on orders of $100 or more. Returns are accepted for 30 days, by mail.
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 - 2Barcode
Listed against the Korean barcode on its box - 3California or Korea
Ships to you from either, as the same Korean-market release
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. The barcode in the specification above is the Korean-market one and it is printed on the box you receive.
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.
Every order ships from California or direct from Korea, 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.
Key benefits
- One patch covers a full zone such as the chin or forehead
- Niacinamide is built into the patch material
- Hydrocolloid absorbs fluid from clustered congestion overnight
- A gentler alternative to pore strips on the nose
Inside the formula
Inside the formula
Reviews
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COSRX Master Patch X-Large
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COSRX, Korean-market original
X-large hydrocolloid patches, 10 ea, with Niacinamide.
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.
COSRX verifies units itself. Find the verification page on cosrx.com and enter the batch number and expiration date printed on your unit. Read them off the package rather than from us, which is the point.
Source: COSRX FAQ
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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