and high quality. Heating side is empty. Red wire to positive, black wire to the negative, it generates electricity when the temperature difference happened Small 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/ C Optimum value (Z): 2.5 ~ 3x10-3W/ OC Model: SP1848-27145 Working Environment: -60~125 degree Lead Length: about 30cm Thermal conductivity (K): 15~16x10-3-W/ C cm Conductivity: 850~1250 -1.cm-1 Product Name: Thermoelectric Power Generator Product material: ceramics Product color: white Product size: 4cm×4cm×0.38cm Product weight: 115g Package Contents: 5x Thermoelectric Power Generator Only 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.