1.DOU BLE SIDED MATERIAL OF HEATING PAD:black waterproof fabric on the front, more comfortable for dirt resistance, white insulation cotton on the back can reduce heat loss, the electric heating pad can be washed, but the interface and other parts are not allowed to enter the water 2. THERMAL INSULATION INNER LAYER:aluminum film pearl cotton material, tight and tight, neatly stitched, will not burst the bag, meticulous workmanship, long term thermal insulation, hot and cold dual use 3.PRECISE TEMPERATURE CONTROL:Our fermentation machine is equipped with a temperature control meter, which can accurately control the temperature up to 0.1C. You can adjust the temperature you want. 4.NO PECULIAR SMELL:This household fermentation machine has no peculiar smell and does not affect the taste of food during fermentation. It has a built in 75°C thermal protection to prevent excessive heat preservation from causing the heating pad temperature to be too and increase product safety insurance