{HEAD ~ The urethane prepolymer} is {TAIL ~ the reaction product} of a dihydroxy functional polyol and an isocyanate 
{ HEAD ~ The urethane prepolymer } is { TAIL ~ the reaction product } of a dihydroxy functional polyol and an isocyanate
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH