{TAIL ~ The gas pressurization system} normally includes {HEAD ~ powered blowers} where a flap like sealing device can be installed to seal gas leakage 
{ TAIL ~ The gas pressurization system } normally includes { HEAD ~ powered blowers } where a flap like sealing device can be installed to seal gas leakage
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH