Articles, e.g. inflated sports balls made of these alloys of polyurethanes and {HEAD ~ rubbers} have {TAIL ~ surprisingly low air permeability} and improved resiliency 
Articles , e.g. inflated sports balls made of these alloys of polyurethanes and { HEAD ~ rubbers } have { TAIL ~ surprisingly low air permeability } and improved resiliency
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH