Piboo
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cecith Waterlock First Serum

Ingredients and claims, checked

Last checked September 13, 2026

Budget for serums

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What is it like at a glance?

What the ingredients do

Hydration leads, with 13 of 36 ingredients. It also contains Sea Salt.

Hydration
13
Moisture seal
3
Skin protection
1
Exfoliation
1

By skin type

  • DryGood fit
  • OilyNeutral
  • CombinationGood fit
  • SensitiveUse with care

Piboo’s rating from user reports.

Worth knowing

  • On pore-clogging lists

Made for

What is this product?

What to expect
It's made for better hydration.
Key ingredients
Jojoba Seed Oil, Hyaluronic Acid, Sea Salt
When
Morning and evening

A serum that dispenses as a foam. It's made with panthenol and sea water. It comes in a 150 ml size.

Who is it for?

Good for

  • Dry skin
  • Combination skin
  • Dehydrated oily skin

Less suited to

  • Sensitive skin

What's good, and what to watch for?

Good points

  • Hyaluronic acid and panthenol add moisture

Watch-outs

  • If you clog easily: Jojoba seed oil

What makes it different?

It contains ten forms of hyaluronic acid.

How do you use it?

Where in your routine
First leave-on step, applied to damp skin straight after cleansing and layered
Pairs well with
  • Whatever normally follows a first essence, unchanged
  • A cream on dry skin, and nothing extra on oily skin
Don't combine with
Applying it to fully dried skin

What is in it?

The full ingredient list as the brand publishes it, in the printed order. Tap a name to read about that ingredient.

This brand publishes its ingredient list in Korean only. Names below are the matching INCI names from the Korean Cosmetic Association ingredient dictionary.

Key ingredientWorth a closer look

Ingredients with no mark are ones we found nothing notable about, and when marks overlap on one ingredient we show the caution first.

What the claims add up to

Only partly backed:
better hydration (amount unknown)
Don't count on:
better barrier support
Tests passed:
hypoallergenic · skin irritation
See each claim, checked (41)

Claims, checked

  • STEP 2 Drawing in moisture: 10-fold hyaluronic acid / With 10-fold hyaluronic acid subdivided by molecular size, a stepwise moisturizing design that fills every skin layer without gapsbacked by evidence
  • Sesed Water Lock First Serum is not a foam for the sake of foaming.backed by evidence
  • Sesed Water Lock First Serum is a bubble created by gently pushing up a two-phase formulation containing oil and water together through the physical structure of a pump container. The foaming is the normal feel of Water Lock First Serum.backed by evidence
  • Unlike high concentrations where cleansing power is expressed, Sesed used only an extremely small amount of 0.3% or less in total, solely for emulsification · stabilization purposes.backed by evidence
  • High-content cleansing surfactants / SLS SLES / ethanol / siliconebacked by evidence
  • Low-irritation test completedbacked by evidence
  • A. If abnormal symptoms or side effects such as red spots, swelling, or itching occur on the used area during or after use of the cosmetic, or due to direct sunlight, consult a specialist, etc.backed by evidence
  • What matters is which surfactant ingredient was used, for what purpose, and how much.backed by evidence
  • Moisture serum that fills, without any chance to dry, the moisture golden time that begins right after facial cleansingplausible, not tested
  • After more than 20 rounds of sampling, we formulated it in a form that delivers stable emulsifying power with the smallest amount.plausible, not tested
  • FSC-certified eco-friendly paper & soy ink for sustainable beauty and forest protectionplausible, not tested
  • We did not compromise. Completed after over a year of development and dozens of rounds of sampling.plausible, not tested
  • For dry skin, layer 5-7 times in small amounts. When reapplied after absorption, the moisture sensation rises even deeper.plausible, not tested
  • For oily/combination skin, lightly layer 2-3 times. Fill with moisture only and finish fresh.plausible, not tested
  • * FSC certification: An international certification with 10 principles and 56 standards including biodiversity preservation of forests, an eco-friendly certification mark granted to paper and goods produced sustainably.plausible, not tested
  • Triple moisture-locking design key to skin barrier improvementpartly backed
  • Sesed's proposed 3-STEP Water Lock system for improving inner drynesspartly backed
  • STEP 3 Locking in moisture: Jojoba oil & Squalane / A step that maintains moisture for a long time by balancing oil and water with jojoba oil and squalanepartly backed
  • Skin irritation index 0.00%partly backed
  • NO artificial colors & fragrances / White, high-concentration formulation realized with efficacy ingredients / Low-irritation formula without added fragrancespartly backed
  • A blend of 10-fold hyaluronic acid, jojoba, and squalane for oil-water balance. A first serum that moisturizes the skin with minerals and aquaporin that open the moisture pathway.partly backed
  • 10-fold hyaluronic acid barrier · moisture serumpartly backed
  • Daily Care: After cleansing, use within 3 seconds while a little moisture remains. It boosts the natural water glow and makeup adherence in one go.partly backed
  • Without a doubt, the world's most perfect skin barrier strengthening solutionoverstated
  • 3 seconds a day ends inner dryness!overstated
  • Definite inner dryness resolution, immediate improvement in just 30 seconds*overstated
  • The No. 1 brand drawing the most attention in 2026, Sesedno supporting source found
  • Sold out nationwide immediately upon entering pharmaciesno supporting source found
  • Real-time sales No.1 noticed by The Hyundaino supporting source found
  • At the moment of application, real moisture that fills from the inside, not the outsideno supporting source found
  • STEP 1 Opening the moisture path: Minerals & Aquaporin / Designed with minerals from sea salt and deep-sea water, a moisture path considering aquaporin, the skin's internal water channelno supporting source found
  • After 30 seconds of use, evaluation of improvement in skin surface moisture, evaluation of improvement in inner dryness (inner moisture)no supporting source found
  • We listened to the many skin concerns of 150,000 friends, used them ourselves, and went through repeated improvement cycles.no supporting source found
  • K-pharmacy sold-out frenzy barrier serumno supporting source found
  • Those who have used it say it is definitely different: irreplaceable, sold-out linesnothing specific to check
  • Chewy bubble completes moisture radiance, new-concept first serum that fills from the skin barriernothing specific to check
  • Skin barrier care routine for resolving inner drynessnothing specific to check
  • Many moisturizers fill, but why is there none that opens the moisture pathway?nothing specific to check
  • No matter how good the ingredients, if the 'path' is blocked, it's useless, so we've fully contained the entire moisturizing process in one bottle, from opening the moisture pathway to locking the balance.nothing specific to check
  • Sesed's clean beauty practicenothing specific to check
  • The standard completed in that process was one: 'Balance that sets the skin barrier right'nothing specific to check

We quote each claim exactly as the brand published it, then check it against the ingredient list and the brand's own documents.

How we check claims

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