The fluid cushion has {TAIL ~ a fluid support surface}, a retractable/deployable bolster, and {HEAD ~ a closure mechanism} 
The fluid cushion has { TAIL ~ a fluid support surface } , a retractable / deployable bolster , and { HEAD ~ a closure mechanism }
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD