{HEAD ~ The sidewalls} 57 typically define {TAIL ~ an obtuse angle} with the bottom surface 55 of the recess 53 
typically define
{ HEAD ~ The sidewalls } 57 typically define { TAIL ~ an obtuse angle } with the bottom surface 55 of the recess 53
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH