Own internal temperature, the surface temperature of 25 degrees maximum, automatic constant temperature system, safe,reliable Usage:Specification:Voltage:220~240/110~120VElectric film:0.3-0.65W/CM2 Pressure Level:>3750V Life:>30000hourFar-infrared wavelengths:8-15μmFull-fat body ratio method:86%Infrared Conversion Rate:68%Size:310×180×130mm PVC-MINI PVC-S PVC-M PVC-L