About the tourmaline glass: The tourmaline glass is made by nano technology and contain 20 minerals. Those minerals can change the normal drink water into alkalescence water in 15 minutes, and produce far frared electromagnetic wave to change the nature of water for human beings to balance. Color: black, brown, white steel, fissured black, fissured brown Function: 1.Neutralize acids of human body for balance. 2.Negative potential of the glass have powerful reducing capacity for anti-oxidation. 3.Subset of the glass have osmotic and solvency force to activate cell, improve metabolism. 4.It contains 20 minerals such as calcium, potassium, magnesium, zinc, selenium, and those are good to human beings. 5.Negative ion of the glass is helpful for bacteriostasis. 6.Safe to use.