Terephthalylidene Dicamphor Sulfonic Acid (TDSA) is a water-soluble, photostable organic UVA filter. It works by absorbing long-wave UVA radiation and converting it into harmless energy, helping protect the skin from UVA-induced photoaging and oxidative damage, while supporting broad-spectrum sun protection.

Highly Photostable, maintaining Protection for long hours.
Strong UVA Filter (Especially UVA1 & UVA2).