Summertime is here, and sunscreen makers are marketing sunscreen products with higher and higher sun protection factor (SPF) numbers on their labels. SPF numbers are supposed to guide users about how long they can stay in the sun, but experts say the label numbers have gotten so high that they have become essentially meaningless. In this article, a reporter talks to experts about specific brands of sunscreen in attempt to help sunscreen users can use these products to best protect their skin.