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