B01EIY6N7C Get ice cold in minutes or heat to boiling by simply reversing the polarity, used for numerous applications from CPU coolers to alternate power sources, or even for your own custom car drink warmer/cooler. Since they consit primarily of semiconductor material sandwiched between ceramic plates and have no moving parts Each device is full inspected and tested Model: TEC1-12706 Size: 40mm x 40mm x 3.8mm