These openings can be holes or {HEAD ~ small bores} extending from {TAIL ~ the top surface} through the bottom surface of the base member 
extending from
These openings can be holes or { HEAD ~ small bores } extending from { TAIL ~ the top surface } through the bottom surface of the base member
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH