Obagi-C Rx SunGuard SPF 30 is a daily used sunscreen that provides broad-spectrum sun protection for healthy skin. This ultra-sheer Z-Cote formula helps aid in the prevention of  sunburn from UVB radiation and protects against long UVA rays linked to deep premature skin-aging. This SunGuard also provides a great deal of sun protection from UVA and UVB damage and against long UVA rays linked to premature aging of the skin while simultaneously protecting the skin's Photolumines quality.