Preferably, {HEAD ~ the film} has a total thickness of from {TAIL ~ about 3 to 20 mils} 
Preferably , { HEAD ~ the film } has a total thickness of from { TAIL ~ about 3 to 20 mils }
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL