The Aluminum used in these purposes is in greater thicknesses than normal. It can also be armored with iron rods to strengthen the filling. As for the glass, it is made specifically for this function and may contain a layer of polypropylene carbon (Polycarbonate) which consists of several layers. The number of layers depends on the type of weapon and the power of the shots that is incurred on the glass and how the glass can prevent the shots, also it depends on the shooting distance, that prevent bullets or broken glass pieces, as a result of shooting on the glass, or from glass shattering on the people and properties