7-Dehydrocholesterol (7-DHC): Usage: Important intermediate for synthesis of Vitamin D3, additive for skin-care cosmestics to prevent from UV radiation and skin disease.Or lab-purpose reagent. Packing: Aluminum bags lined with food grade PE bags, packaged in paper cartons. Stability and storage: Stored under dry, cool and dark condition and avoid moisture, water or heat. The shelf life is 6 months.