Large Fit Over Sunglasses Flat Black Frame Mirrored Copper Lens. Fit overs are specifically designed to fit over prescription eyewear. The design allows fit-overs to float above your prescription eyewear. Most fit-over wearers forget that they are even wearing two pairs of glasses. All of the fit-over models are manufactured of ultra-lightweight materials. Fits over glasses up to 50mm x 146mm.