The projection extends from {HEAD ~ a rim} of the hole and {TAIL ~ the hollow} is in communication therewith 
The projection extends from { HEAD ~ a rim } of the hole and { TAIL ~ the hollow } is in communication therewith
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH