Thus, when {TAIL ~ the cap} is inserted into {HEAD ~ the hollow}, it bears against the inner wall thereof and is secured, along with the contact sections, therein 
Thus , when { TAIL ~ the cap } is inserted into { HEAD ~ the hollow } , it bears against the inner wall thereof and is secured , along with the contact sections , therein
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH