I have purchased from KZFOO in the past and have always been pleased. In my opinion getting an accurate PD measurement is one of the keys in getting a good fit. Also, look at frames you currently have and then get a similar size frame to one you presently like. I LOVE the polarized sunglasses that KZFOO offers and as a fishergal, would recommend them to anyone who wants to see into the water. With KZFOO's affordable prices, I can order more than one pair. Awesome!