The gasket is a non-porous deformable material that is installed between the belt attachment flange and the fabric belt. The gasket allows a gas-tight seal when the back-up bar clamping action is applied.
![Rectangular fabric expansion joint](https://usbellows.com/wp-content/uploads/1990/07/fabric-expansion-joint-2-300x224.jpg)
The gasket is a non-porous deformable material that is installed between the belt attachment flange and the fabric belt. The gasket allows a gas-tight seal when the back-up bar clamping action is applied.