A method 1, wherein {TAIL ~ the metal} made Raschig rings are made of {HEAD ~ stainless steel} 
A method 1 , wherein { TAIL ~ the metal } made Raschig rings are made of { HEAD ~ stainless steel }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD