LENS: ANTI BLUE LIGHT – Harmful blue light refers to the 415-455 nanometer range of the visible light spectrum. DOOViC blue light filter reading glasses lenses can block about 95% harmful blue light,but do not block all blue ray. So doovic computer reading glasses excellent for smartphone/tablet/monitors and LED lighting emit short-wave blue light
BENEFIT: WEAR BLUE LIGHT GLASSES – Less eye strain,better sleep,fewer headaches,reduced risk of eye diseases and you can avoid many of these issues related to blue light by stepping away from your computer, reading a book instead of watching TV, and limiting the use of your tablet and phone
HINGE:FLEX HINGES – Doovic hinges are equipped with a small spring that affords the arms a greater range of movement and does not limit them to the traditional, 90 degree angle. Compare with Standard Hinges,Spring hinges glasses require less adjustments, provide a comforting squeeze for the wearer and are more able to withstand everyday use
SERVICE:ACCESSORIES and AFTER-SALES – This black thick frame reading glasses 1.0 came with a hard case, cleaning cloth, neck lanyard and a keyring with a tiny glasses screwdriver tool attached with reversible shaft for both cross-head and flat screws.And if any question, please to contact me or contact amazon customer service,we will reply you within 75 hours