To minimize {HEAD ~ these performance deficiencies} in materials used to limit air permeability, special material formulations have been developed that comprise, preferably, {TAIL ~ an amorphous polyurethane based elastomer/rubber alloy} 
To minimize { HEAD ~ these performance deficiencies } in materials used to limit air permeability , special material formulations have been developed that comprise , preferably , { TAIL ~ an amorphous polyurethane based elastomer / rubber alloy }
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL