The Emergency Air Seal will thread between the adapter and the shaft seal.  It is to be inflated when there is damage to the shaft seal that causes flooding.  

     The AXU Air Seal Adapter includes a specially designed air seal ring that can be inflated with air to provide a temporary static seal.  An Adequate seal should be obtained with about 15 PSIG air pressure.  Do not rotate the shaft while the air seal is inflated.