The loop yarn can be {HEAD ~ a spun yarn} made by any available spinning technique, or {TAIL ~ a filament yarn} made by extrusion 
The loop yarn can be { HEAD ~ a spun yarn } made by any available spinning technique , or { TAIL ~ a filament yarn } made by extrusion
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH