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Tetrapeptide-21

What Tetrapeptide-21 is & what it does

Tetrapeptide-21 is a synthetic signal peptide built from a short chain of four amino acids. It is commonly used in anti-aging and firming skincare, where peptides of this type are intended to support the look of smoother, more even skin over time. It is not a UV filter and offers no sun protection. It carries no flagged concerns in this catalog and is used at low concentrations.

What is Tetrapeptide-21?

It is a synthetic signal peptide made of four linked amino acids, used in skincare at low concentrations. Peptides like this are common in anti-aging and firming products.

What does Tetrapeptide-21 do in skincare?

It is generally used to support the look of smoother, firmer, more even skin over time. It is not a UV filter and provides no sun protection.

Is Tetrapeptide-21 safe?

Peptides of this type are widely used and well tolerated, and no concerns are flagged for it in this catalog. It is typically present at very low levels.

Sunscreens with Tetrapeptide-21

We rate 5 sunscreens that contain it:

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