GAMMA RAY FLEXLITE GR OG-001 Computer Reading Glasses in Ergonomic Memory Flex Frame with UV Protection, Anti Blue Light, Anti Glare and Scratch Resistant Lens in 53-16-140 Size - 2.50x composite frame plastic lens non-polarized Lens width: 53 millimeters Amber tinted lenses to minimize Digital Eye Strain caused by harmful blue light emitted from digital screens Great for alleviating visual fatigue and discomfort from long periods of web surfing, gaming and working under fluorescent lights Ultra light weight and flexible TR90 frame material for long term use and durability Includes frame carrying case and cleaning cloth Your computer reader magnification/power depends on how far you are from the screen you are viewing. For a laptop or desktop about 19+ inches away, select a magnification HALF your normal reading power. For a smartphone, tablet or a book about 12 to 18 inches away, select your normal reading power