The preferred form of {HEAD ~ the shield} has {TAIL ~ the flexible band} formed of elastomeric material 
The preferred form of { HEAD ~ the shield } has { TAIL ~ the flexible band } formed of elastomeric material
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH