This is {HEAD ~ a very important advantage} compared with {TAIL ~ the conventional manufacture} of conical coils by winding up onto a conical mandrel 
This is { HEAD ~ a very important advantage } compared with { TAIL ~ the conventional manufacture } of conical coils by winding up onto a conical mandrel
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH