What is the material of the cell phone airbag?

The airbag support structure of bubble mobile phone is composed of several rubber soft bags filled with compressed air, which is used to support the top and bottom plates and isolate the support structure of goaf. The airbag layer of the bracket can be extended and retracted up and down, and can be switched between three gears at will, and can also be rotated 360 degrees at will. Mainly the material, don't buy a cottage! !