A glass protector is an additional sheet of material—commonly polyurethane or glass—that can be attached to the screen of an electronic device and protect it against physical damage. AR coatings are used for tempered glass screen protectors (though not all tempered glass screen protectors come with AR coating). It is hardly noticeable, and colors and contrast look almost the same. As mentioned above, over time, the coating will rub off, or scratch off, and will significantly reduce the anti-reflectiveness. Devices with an AR coating need to be treated with extra care. A monitor screen that is treated to reduce glare from light sources. LCD screens originally had a non-glare matte finish, which was one of their significant benefits over CRTs. By the turn of the century, LCD screens used an overlay that enhanced colours but were once again reflective. Screen protectors are made of either plastics, such as polyethylene terephthalate (PET) or thermoplastic polyurethane (TPU), or of tempered glass similar to the original tablet or smartphone screens they are meant to protect. Plastic screen protectors cost less than glass and are thinner, around 0.1 mm (0.004 in) thick, compared to 0.3 to 0.5 mm (0.012 to 0.020 in) for glass. At the same price, glass will resist scratches better than plastic, and feel more like the device’s screen, though higher priced plastic protectors may be better than the cheapest tempered glass models. PET film products are the best choice for basic screen protection. TPU protectors can be a bit rare, but they have the best ratio of affordability and toughness. Finally, Tempered Glass protectors offer the ultimate in protection and feel, but they are the priciest of the bunch. Still, even the most expensive ones make sense for flagship smartphones and tablets. A glass protector is superior to its alternatives in every way. It has better light transmittance, making for a clearer display. It’s anti-reflective and glare reducing. It has oleo phobic coating, which heavily reduces fingerprints. It has the smooth feel of actual glass under your fingertips. Unlike Gorilla Glass, it resists sand scratches, making it the only viable option for beachgoers.