NoIR filters can help people minimize eye discomfort and maximize visual resolution. Filter shade number 21‚ medium gray‚ allows in 32% of visible light, has 100% ultraviolet protection and has a soothing color which sharpens focus and provides excellent glare protection. It is often recommended for people with post-operative cataracts or glaucoma. The SpectraShield frame is a fit-over style frame with a more contemporary design. The glasses have side lenses to let in additional light while managing those effects.