Broad Spectrum UVA/UVB Block Spf 30 The greatest cause of skin damage, premature aging and skin cancer, is exposure to the sun s ultraviolet rays. This distinctive sunblock formulation is rooted in state-of-the-art photo protection science. Microfine Zinc-Oxide serves as a broad spectrum block that inhibits UV ray penetration. Alistin protects against cell membrane damage, and lipisomes A, B, C and E fend off sun-induced free radical activity.