This material may exit through {HEAD ~ a lower opening} 28 defined by {TAIL ~ the lower rim} 22 
defined by
This material may exit through { HEAD ~ a lower opening } 28 defined by { TAIL ~ the lower rim } 22
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH