This is a thermostatic coaster, cold water cannot be heated. Product name: Constant temperature heating coaster. Material: ABS+electronic components. Power on method: USB plug. Line length: 0.9 meters. Rated power: 20W. Input: 5V/2A. Product size: diameter 11.2cm. Product thickness: approximately 2.4cm. Product color: pink/green/white. Heating plate diameter: 8.8cm. Temperature range: three levels: 55 degrees/65 degrees/75 degrees.