This is a 710ml Drink Glass Made of Pp Material. When It Comes into Contact with Water, It Changing Color This Water Cup Adopts a Special Technology That Makes the Color of the Cup Change Under the Action of Water. This Color Change May be Due to Some Kind of Reactive Substance Inside That Undergoes a Chemical Change When Water Comes into Contact, Causing the Color to Change. in Addition, the Logo Can Also be Printed on the Surface of the Water Cup, Which Provides a Customized Opportunity for Enterprises, Groups or Individuals to Print Their Brand or Logo on the Water Cup, So as to Achieve Publicity & Display During Use.