Firmoo Blue-light Blocking Lens - The light yellow tint lens effectively block harmful blue-light from computer, phone, iPad, etc, relieving visual fatigue. | MAGNIFICATION - These glasses are +2.50 magnification. Your reader magnification/power depends on how far you are from the screen you are viewing. For a laptop or desktop (19+ inches away) select a magnification 2/3 your normal reading power. (eg:Your normal power is +3.00, then choose +2.00 for this case) For a smartphone, tablet or a book about select your normal reading power. | PRODUCTS DIMENSION -Please check the size before your purchase. Frame material: TR90, Lens width:53mm , Frame width:131mm, Lens height:38mm, Bridge (DBL): 18mm, Temple length:142mm, Lenses: Non-Aspheric, Head size: Narrow | VINTAGE STYLISH FRAME- Fashion and Chic Cateye frame, avoid the enbarrassment of wearing reading glasses and give you more energy via looked samrt. | Package Include & Warranty: The package includes 1* Anti-bluelight glasses, 1*plastic case, 1*cleaning cloth. Unfit or wrong glasses can be exchanged or refunded within 90 days of receiving. Customers will enjoy A Life Time warranty, covering any possible defect in materials and workmanship