O.TWO.O Waterproof Liquid Eyeliner – Ultra Fine 12-Hour Black

Meet your new go-to liner: the O.TWO.O Ultra Fine Liquid Eyeliner. Engineered for bold, precise definition, this professional-grade pen delivers streak-free lines in a single confident stroke — whether you're going for a subtle everyday look or a dramatic cat-eye wing.

This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Why You'll Love It

• 12-Hour Long-Lasting Wear: Continuous-flow ink formula keeps your look intact all day and into the night.
• Waterproof & Smudge-Proof: Advanced waterproof film technology locks colour in place so your liner stays exactly where you put it.
• Quick-Drying Formula: Dries on contact for crisp, clean lines — no smearing, no waiting.
• Ultra-Fine Flexible Tip: The hair-thin precision tip flexes with your hand, letting you control line thickness from a razor-thin flick to a bold, graphic stroke — perfect for beginners and pros alike.
• Intensely Pigmented Carbon Black: Rich, deep black colour with up to 300 metres of smooth, continuous ink flow thanks to the carbon black formulation.
• Anti-Coagulation Ball Design: A built-in stirring ball prevents ink from settling, ensuring consistent, even output every time you use it.

Key Features

• Formulation: Liquid
• Colour: Intense Black
• Net Weight: 0.5 ml / 0.5 g
• Shelf Life: 3 Years (36 months after opening)
• Wear Time: Up to 12 Hours
• Tip: Ultra-fine hair-tip precision nib
• Waterproof: Yes

Full Ingredient List

Acrylates Copolymer, Water, Styrene/Acrylates Copolymer, CI 77266, 1,2-Hexanediol, Butylene Glycol, Laureth-21, Aloe Barbadensis Extract, Methylparaben, Sodium Dehydroacetate, Ethylhexylglycerin.

How to Use

1. Shake gently before use to activate the anti-coagulation ball for smooth ink flow.
2. Start from the inner corner of the eye and glide the ultra-fine tip along your lash line.
3. Apply light pressure for a fine line; press slightly more for a bolder stroke.
4. For arrows or a cat-eye flick, angle the tip upward at the outer corner and draw your desired shape.
5. Allow a moment to dry — the quick-dry formula sets almost instantly.

What's in the Box

• 1 × O.TWO.O Ultra Fine Liquid Eyeliner Pen (Black)

Made in China.

Complete Your Eye Look

Pair this liner with these fan favourites from our store:

• 0.3ml & 0.5ml Ampoule Head Cap Adapter for Hyaluron Pen
• 0.3ml & 0.5ml Hyaluron Pen Ampoule Head Cartridge | Skin Care

Expert Reference

For guidance on evaluating cosmetic ingredients and safety, visit the U.S. Food & Drug Administration – Cosmetics page.

Frequently Asked Questions

Q: Is the O.TWO.O liquid eyeliner truly waterproof and smudge-proof?

A: Yes! The O.TWO.O liquid eyeliner uses a waterproof film smart-lock technology that seals the ink on contact with your skin. It is formulated to resist water, humidity, and everyday wear for up to 12 hours without smudging or fading.

Q: Is this eyeliner suitable for beginners?

A: Absolutely. The ultra-fine flexible tip is designed to be beginner-friendly — it flexes gently with the natural movement of your hand, making it easy to draw smooth, even lines even if you're new to liquid liner. You can build from thin to bold lines simply by adjusting your pressure.

Q: How do I remove the O.TWO.O liquid eyeliner at the end of the day?

A: Although the formula is waterproof, it can be removed with a gentle oil-based makeup remover or micellar water. Apply to a cotton pad, hold briefly against the liner to dissolve it, then wipe away gently without rubbing.

Q: What is the shelf life of this eyeliner?

A: The O.TWO.O liquid eyeliner has a shelf life of 3 years (36 months after opening). Store it with the cap tightly closed in a cool, dry place away from direct sunlight to maintain optimal performance.