Mobile Shield Walls are constructed of 1" - 4" thick lead encased in stainless steel. There are nine interlocking panels: seven panels that are 11' 6" tall and two panels that are 8' 6" tall. Each panel is equipped with a handle for moving into position and rolls on two inline wheels. The floor track is a key locking design with three direction changes and there are two top end tracks to steady the panels. The tracks are adjustable to align with the floor.