INSTANT 20/20™ EYEGLASSES—THE PERFECT SPARE PAIR! Variable focus eyewear is an ideal temporary solution to lost or broken eyeglasses or contact lenses. Just turn the dial to easily adjust the focus in each lens to suit your vision needs. Covers a wide range of powers and corrects 90% of spherical refractive errors. One size fits all. Have your eyes examined regularly by an optometrist or ophthalmologist. These eyeglasses are not prescription lenses and do not correct astigmatism. Carry case included.