The combination of the cap and {TAIL ~ connecting sections} is inserted into {HEAD ~ the hollow} which is provided with an opening through its cover 
The combination of the cap and { TAIL ~ connecting sections } is inserted into { HEAD ~ the hollow } which is provided with an opening through its cover
OTH OTH OTH 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