This type of frame slightly bigger than normal frame. Instead of plastic hinges we can use aluminium hinges and instead of plastic stopper we can use male and female magnetic strip be used to lock the frame. It gives extra grip and withstand windforce. Also we can use weather strip to inside and outside of the frame. The purpose of weather strip can cover the gape between frame and window. In this type, we mostly used black coated SS 304 for better look and long losting life.