Biosilk Silk Therapy is a weightless, leave-in, refreshing hair restorer, enriched with silk. Biosilk Silk Therapy repairs, soothes and protects all hair types. Not tested on animals. Biosilk Silk Therapy is a unique product that improves both the structure and shine of the hair. Silk Therapy is suitable for normal and damaged hair. Strengthening: Silk binds and repairs hair from the inside out. Silk is very strong, by comparison it is stronger than steel. Silk strengthens the hair and gives it more body and volume. Moisture-regulating: Silk can hold three times its own weight in moisture. Silk provides elasticity. Silk ensures a long shelf life of the styling and color results. Silk is great for skin care. Silk provides incredible shine and reflection. The molecular shape of silk is a pyramid shape that provides a three-dimensional shine. Protection: against heat, cold, moisture and UV radiation. Against pollution. Silk molecules attract and retain color, thus ensuring a longer shelf life of the hair color.