Feature Colding side posts with the wordsHeating side is emptyRed wire to positive black wire to the negative it generate electricity when the temperature difference happened Specification Model SP1848 27145 Color whiteLead Length about 30CMSize 40MM x 40MM x 3 4MM 20 degree temperature difference open circuit voltage 0 97V generated current 225MA 40 degree temperature difference open circuit voltage 1 8V generated current 368MA 60 degree temperature difference open circuit voltage 2 4V generated current 469MA 80 degree temperature difference the open circuit voltage 3 6V generated current 558MA 100 degree temperature difference open circuit voltage 4 8V generated current 669MA The above values are for reference only the wiring in actual use and the step up board there will be loss of current Package included 1 x 40x40mm thermoelectric power generator peltier module