My husband's old glasses came with a magnetic sunglass attachment but when he got a new frame, the sunglass part was no longer available. These were the next best option. He likes them over clip ons because he can flip them up easily when he wants to write something down in his vehicle (he's a courier). We bought this larger size because it covers his glasses fully with a little overlap. Beats him wearing those HD Vision sunglasses in public LOL.