Our clip-on sunglasses come in polarized and non-polarized UV400 lenses. Polarized lenses reduce glare, they make your vision appear sharper and clearer. Polarized lenses are lighter weight on your frame which makes them more comfortable to wear. Non-polarized lenses make it easier to see your digital devices, (LCD) screens, cell phones and car dashboards. Clip-ons have hooks which are designed to hook onto your frame with a spring in the middle for tension. The attachment hooks have rubber or plastic coatings to help protect the lenses. We do not recommend clip-ons for rimless or semi-rimless glasses.