The watch lens composed of sapphire components is scratch resistant, drop resistant, and corrosion-resistant, and can withstand strong water pressure even when swimming shallow underwater. Sapphire glass is commonly known as synthetic sapphire, and sapphire mirrors are generally made by processing and upgrading sapphire glass. It uses fine and precise alumina powder as raw material, and then condenses into crystal blocks in corresponding high-temperature furnaces, with high hardness. In addition to being used on watch mirrors, there are also some phone windows that can be used as it.