Alignment hole 17 is also in {HEAD ~ the shape} of {TAIL ~ a comer} cut out 
of
Alignment hole 17 is also in { HEAD ~ the shape } of { TAIL ~ a comer } cut out
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH