Combination 1, wherein {HEAD ~ the Shore D hardness} of {TAIL ~ the plastic material} is approximately 15 25 
Combination 1 , wherein { HEAD ~ the Shore D hardness } of { TAIL ~ the plastic material } is approximately 15 25
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH