Specifications ·Type: Negative ion anti-Blue glasses ·Anti-blue light rate: 70% ·Frame Color: Black ·Len’s Color: light yellow ·Material:TR+Negative ion material/frame Resin/lens ·Lens width: 50mm ·Lens height: 42mm ·Frame width: 135mm ·Leg’s Length: 137mm ·Bridge (DBL): 18mm ·Package: 1 Pair of Glasses ·Magnification Strength: 0 Diopters ＊Why use anti-blue lenses? The main source of blue light is the LED backlight used in the LCD screen. The products with harmful blue light in our daily life are mainly mobile phones, computers, tablet computers, TVs, game consoles, etc. Blue light can penetrate the retina of the human eye and the lens directly to the macular area of the fundus. The anti-blue light lens has multi-layer coating, which can block harmful blue light, protect your eyes and bring you a healthier life.