bellow covers/accordion covers is made up with nylon cloth,plastic cloth fabric or synthetic rubber through folding.Sewing or pressing under high temperature.There is PVC board inside to support it,so that it can endure high temperature can reach 400C and the fastest speed can reach 100m/min.
The enduser could tell us :Length after drawing,Length after compression,Total width of the shield,Interior width of the shield,,Total height of the shield,interior width of the shield.