Thereafter, {HEAD ~ a quantity} of {TAIL ~ primer material} is positioned within the tubing through the second, open end thereof and deposited on an internal bottom surface of the tubing 
of
Thereafter , { HEAD ~ a quantity } of { TAIL ~ primer material } is positioned within the tubing through the second , open end thereof and deposited on an internal bottom surface of the tubing
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH