If you have a HUGE head then these should work great. I wear 7 3/4 hat and their still too loose. Other than that besides some small design flaws that aren't a deal breaker their great quality and the lenses are awesome. Just don't buy unless your head is XXLUpdate:I don't think head size matters with these and here's why: on my head the legs bow out because the frame is too small for my head and their still too loose! And if your head was smaller to fit the small frame they'd obviously still be too loose!Another update is that the top corners come come away from your face so the sun comes in if your at the right angle.I like these glasses for driving and social events because they look good, the blue lenses have deep color and makes other cheap colored lenses look like junk, and they are comfortable and can be worn for long periods.In a nutshell with these glasses, their good looking and high quality but not very functional for any activitys due too looseness and being delicate.