... 3,convinience 4,good quality 5,elegant apperance 1,The shutter door,roller shutter door adopts new material of aluminum alloy, the double layer ... function of prying resistant.2,The surface of the roller shutter door conduct oxidation processes and painted in the condition of high ... power failure also. 5,The opening speed of the roller shutter door,shutter door can up to 0.1m/s,which save the power ...