In order to ensure that the surveillance camera can work normally under the harsh environment of high, low temperature, sand, rain, ice and snow, it will generally adopt various protective covers to extend its working life. The protective cover must protect the camera and lens from It is contaminated by dust, impurities and corrosive gases. At the same time, it must be able to cooperate with the installation site to achieve the purpose of preventing damage. Secondly, the protective cover should be equipped with heaer pad. polyimide heater pad and silicone heater pad are commonly used. The heater pad is thin, soft, and can be customized in shape. It can be installed near the lens without affecting the installation, and will not block the lens. It will be heated in a lower temperature environment to raise the internal temperature of the shield and ensure the camera/lens work normally. The built-in or external fan can circulate the air inside the hood and reduce the temperature inside the hood. In the place where there is less wind and sand, it is also necessary to configure the washer to clean the window glass at any time with the wiper to ensure the image monitoring effect.