Bestseller

Restore the look of skin radiance in just 7 days* with cult-favorite C-Tetra.

Formulated with a stabilized form of vitamin C (7%) called tetrahexyldecyl ascorbate, this lightweight serum works to visibly brighten uneven skin tone and reduce the look of fine lines and wrinkles, while remaining gentle on sensitive skin.

Fortified with vitamin E, this antioxidant powerhouse also helps to promote a more youthful and healthy-looking complexion overall. The perfect option for those who are new to vitamin C, or those with sensitive skin.

C-Tetra™

Lipid 7% Vitamin C Radiance Serum Full Details

Size: 1.0 FL. OZ. (30mL)

Product variants

C-Tetra™

PROVEN RESULTS

7 days to improved skin radiance*
7 days to visibly brighter, smoother skin*
96% of sensitive skins agreed C-Tetra was gentle on the skin*
4 weeks to visibly reduced wrinkles & dark spots*
90% agree skin feels instantly softer*

*Proven via independent consumer study conducted over 4 weeks on 52 participants with sensitive skin.

KEY BENEFITS

Increased Skin Youthfulness

Proven to simultaneously smooth the look of fine lines and wrinkles while visibly boosting skin glow and radiance.
Brighter, More Even Complexion

Proven to visibly brighten the skin tone, for a more even and healthy-looking skin appearance.
Lightweight Nourishment

This jojoba (pronounced 'huh-hoh-ba') seed oil-based formula delivers effective yet non-greasy nourishment for visibly softer and comforted skin.

HOW TO USE

Step 1

After cleansing in the morning, massage 4 drops across the face, neck and décolletage.

Step 2

As part of our CSA Philosophy, we recommend using vitamin C plus sunscreen in the morning and vitamin A at night.

Not sure what order to layer your serums? Take our serums layering guide quiz here.

KEY INGREDIENTS

7% Stabilized Vitamin C (tetrahexyldecyl ascorbate)

A low-irritation form of antioxidant vitamin C that works to keep the appearance of fine lines and wrinkles at bay. It also helps to visibly brighten and even the skin tone for visible dark spot reduction.
Vitamin E

A powerful antioxidant, vitamin E works to deeply nourish and soften the complexion.
Full Ingredients

THE SCIENCE BEHIND THE FORMULA

Ultra-gentle & perfect for visibly radiant skin.

DANIEL ISAACS Chief Product Officer

It is exceptionally difficult to formulate a vitamin C serum that will retain its power over time. That's because vitamin C is notoriously unstable, meaning its effectiveness can be compromised when it comes into contact with light, heat or air. That's why we have chosen to formulate C-Tetra with an extremely stable form of vitamin C (tetrahexyldecyl ascorbate), so you can be sure that your vitamin C is still as potent and effective 6 months after you first opened it.

GOOD TO KNOW

NO ARTIFICIAL FRAGRANCE
NO SYNTHETIC COLORS
PARABEN FREE
CERTIFIED BY THE VEGAN SOCIETY

FAQS

What's the difference between C-Tetra and C-Tetra Luxe?

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C-Tetra is our original, best-selling vitamin C serum. It's the perfect option for those who are new to vitamin C or those with sensitive skin, who still want visible age-defying results. C-Tetra Luxe is our supercharged vitamin C serum - ideal for those looking for clinical brightening and nourishing power. Both serums are formulated with stabilized tetrahexyldecyl ascorbate.
Can I use C-Tetra alongside retinoids?

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Absolutely. In fact we recommend the daily use of these 2 powerful actives as our proven pairing for more youthful-looking skin. Apply vitamin C in the morning and vitamin A at night for proven age-defying results.
Can I use C-Tetra if I'm pregnant or breastfeeding?

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As a cosmetics company, we are unable to provide product advice in relation to medical conditions such as pregnancy. We would recommend discussing the ingredients with your physician or obstetrician before use. As general guidance, this product does not contain any ingredients which we would recommend to avoid during pregnancy, unless advised by your physician.

SUSTAINABILITY CLAIMS

Provenance provides confidence for sustainability claims; helping to prevent ‘green-washing’ and empowering conscious consumers to purchase in line with their values. Provenance ‘Proof Points’ are all third party verified and evidenced through supply chains.

C-Tetra™

Explore the C-Tetra Range

Texture
	NEW C-Tetra™ Advanced Gel-Serum	C-Tetra™ Luxe	C-Tetra™
Texture	Texture Lightweight Gel-Serum	Texture Rich Oil	Texture Lightweight Oil
Key Ingredients
Key Ingredients	Key Ingredients 20% Tetrahexyldecyl Ascorbate Phyto Exosomes Acetyl Zingerone	Key Ingredients 14% Tetrahexyldecyl Ascorbate Squalane Maracuja Oil	Key Ingredients 7% Tetrahexyldecyl Ascorbate Vitamin E
Skin Types
Skin Types	Skin Types All skin types, especially oily & combination	Skin Types Dry Skin	Skin Types Sensitive Skin
Benefits
Benefits	Benefits Brightening Age Defense Skin Nourishment Dark Spot Reduction Smooth & Even Complexion	Benefits Brightening Youth Boosting Skin Nourishment Dark Spot Reduction	Benefits Brightening Skin Nourishment

Dermatologist Recommended

Clinical Results

Age-Defying Experts

Made in the UK

B Corp Certified

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C-Tetra™

Lipid 7% Vitamin C Radiance Serum Full Details

Sorry, this product is currently out of stock

PROVEN RESULTS

KEY BENEFITS

Increased Skin Youthfulness

Brighter, More Even Complexion

Lightweight Nourishment

HOW TO USE

Step 1

Step 2

KEY INGREDIENTS

THE SCIENCE BEHIND THE FORMULA

GOOD TO KNOW

FAQS

What's the difference between C-Tetra and C-Tetra Luxe?

Can I use C-Tetra alongside retinoids?

Can I use C-Tetra if I'm pregnant or breastfeeding?

SUSTAINABILITY CLAIMS

Explore the C-Tetra Range

Complete Your Regime