Apparatus 7, in which each tube is extruded to form separate integral ducts {TAIL ~ each} adapted to house {HEAD ~ a strand} 
Apparatus 7 , in which each tube is extruded to form separate integral ducts { TAIL ~ each } adapted to house { HEAD ~ a strand }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD