and high quality.Heating side is empty. Red wire to positive, black wire to the negative, it generates electricity when the temperature difference happenedSmall and , convenient for use.Designed specifically for power generation. Sealed for moisture protection and contain thermal elements formulated for optimum Seebeck power generation.High temperature 150°C, with NM static protection.Temperature electromotive force (a): 190x uV/ COptimum value (Z): 2.5 ~ 3x10-3W/ OCModel: SP1848-27145Working Environment: -60~125 degreeLead Length: about 30cmThermal conductivity (K): 15~16x10-3-W/ C cmConductivity: 850~1250 -1.cm-1Product Name: Thermoelectric Power GeneratorProduct material:ceramicsProduct color: whiteProduct size: 4cm×4cm×0.38cmProduct weight: 92gPackage Contents:4x Thermoelectric Power GeneratorOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.