The recess 53 typically also comprises {HEAD ~ one or more sidewalls} 57 extending upwardly from {TAIL ~ the bottom surface} 55 
extending upwardly from
The recess 53 typically also comprises { HEAD ~ one or more sidewalls } 57 extending upwardly from { TAIL ~ the bottom surface } 55
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH