The protection against solar UVA and UVB rays is measured by the SPF rating. Sunscreens with an SPF over 15, offer broad spectrum protection against both UVA and UVB radiation. Since iS Clinical sunscreens are sold internationally, they also conform to international requirements that document they convey broad spectrum UVA and UVB protection. The amount of solar protection conveyed by a cream/lotion and a powder sunscreen may be the same, if the SPF rating is the same number. PerfecTint Powder SPF 40 offers the advantage of convenience of application and the ability to take the product while on the go – for sports, family outings, outdoor activities, travel, etc.