{HEAD ~ The yarn} is fed through a hole in the wall of {TAIL ~ the tube} from a groove on the outer surface 
{ HEAD ~ The yarn } is fed through a hole in the wall of { TAIL ~ the tube } from a groove on the outer surface
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH