I live in Arizona which has unmitigated sun all year. I used to put clip-on sunglasses on top of sunglasses just to get a dark enough effect. Weird, huh? Anyhow, buying these sunglasses has freed me from all that, and I can hike in the sun until the cows come home! And, you poor folks who get migraines? Buy these. You can look all over  and never find a pair that shade your eyes as well. I bought like 6 of these cuz I'm afraid they'll run out!