Our Swing Sash Window is an Inside Mount, single pane glass window. It sits flush on the inside of the blind and has a 1/2 inch weatherstripping around the inside frame. The window is installed with two brackets (to hold it in) and 4 swivel clips (2 to keep it closed, 2 to hold it open up top. Each swing sash window will come with all the hardware needed (2 brackets, 4 swivel clips) except the screws. *We recommend a rain guard or awning over the top of this one style window as it does not fully seal like our framed windows.