Hyper Acid4 AHA BHA PHA LHA 30 Serum 20ml (Wash-off)

Not on the ingredient list below: fragrance or parfum, denatured or SD alcohol, essential oils, silicones, parabens, sulfate surfactants, mineral oil or petrolatum and added color.

Full INCI (26): Water, Gluconolactone (14.48%), Lactic Acid (10.12%), Methylpropanediol, Glycolic Acid (4.9%), Potassium Hydroxide, 1,2-Hexanediol, Diethoxyethyl Succinate, Glycerin, Xanthan Gum, Polyglyceryl-10 Laurate, Acacia Senegal Gum, Polyglyceryl-10 Myristate, Glyceryl Caprylate, Niacinamide, Salicylic Acid, Allantoin, Disodium EDTA, Ethylhexylglycerin, Peat Water, Citric Acid, Hydroxypropyl Methylcellulose, Capryloyl Salicylic Acid, Butylene Glycol, Potassium Sorbate, Charcoal Powder

Ingredient list read from incidecoder.com on 30 August 2026.

25 of 26 explained

Water solvent

Water is the base almost every serum, toner and cream is built on. It dissolves the water-loving ingredients and sets how light the finished texture feels. On an INCI list it is usually first, which only means it is the largest single ingredient by weight.

Gluconolactone (14.48%) exfoliant

Gluconolactone is a PHA, the gentlest exfoliant class. Its molecule is too large to penetrate quickly, so it smooths the surface without the sting of an AHA, and it is a humectant at the same time.

Lactic Acid (10.12%) exfoliant

Lactic Acid is a larger AHA than glycolic, so it works nearer the surface and is easier on skin, and it is a humectant as well as an exfoliant. It is the AHA of choice for dry skin.

Methylpropanediol humectant

Methylpropanediol is a small glycol used to hydrate and to help water-soluble actives penetrate the outer layer of skin more evenly. It leaves almost no tack, which suits watery textures.

Glycolic Acid (4.9%) exfoliant

Glycolic Acid is the smallest AHA, which is why it is also the most penetrating and the most likely to sting. It loosens the bonds between dead surface cells and is used for the look of dullness and rough texture.

Potassium Hydroxide pH adjuster

Potassium Hydroxide is a strong base used in traces to raise a formula to its target pH. In a soap-style cleanser it also converts fatty acids into the surfactant that does the cleansing.

1,2-Hexanediol humectant

1,2-Hexanediol is a glycol used for two reasons: it holds water like glycerin, and it makes a formula harder for microbes to live in, so less traditional preservative is needed. Korean formulas use it heavily for that second reason.

Diethoxyethyl Succinate solvent

Diethoxyethyl Succinate is a solvent that helps water-resistant actives spread and sink in evenly. It also leaves a light, silky feel.

Glycerin humectant

Glycerin is the most used humectant in skincare. It draws water into the outer layer of skin and holds it there, and it is one of the very few ingredients whose hydrating effect is settled science rather than marketing. Higher amounts feel tacky, which is why it is usually blended.

Xanthan Gum thickener

Xanthan Gum is a polysaccharide made by fermenting sugar. It thickens a watery formula into a gel and holds the whole thing in suspension so nothing separates. Too much of it and a serum turns stringy, which is why it appears in fractions of a percent.

Polyglyceryl-10 Laurate emulsifier

Polyglyceryl-10 Laurate is a sugar-derived emulsifier and solubiliser, mild enough to be a standard choice in Korean essences. It dissolves small amounts of oil into water without any tightening feel.

Acacia Senegal Gum film former

Gum arabic, tapped from the acacia tree. It thickens, forms a tightening film as it dries, and holds pigments in place.

Market

Korean market, the version sold in Korea

Made in

Republic of Korea

Volume

20ml

Category

Exfoliator

Actives

Allantoin, Glycolic Acid, Lactic Acid, Niacinamide, Salicylic Acid

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.

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.

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.