VFD Character: VFD digital micro-intelligent computer control, with colorful dynamic display of fluorescent screen & can control the humidity automatically. Water tank: Back installed water tank, non-touch sensory switch, alarm out when the tank is full. (Chinese patent) Defrosting Function: Can display different state of: Frost up, under Defrosting, and can control the defrosting time according to the different temperature Protective Function: Has Super& low Voltage, Super-Temp. Protection device, can alarm with different indicating light according to different situation.