Applying {HEAD ~ a slight downward pressure} on {TAIL ~ the squeegee support} causes the rubber edge to press against the flat surface of the crystal wafer 
on
Applying { HEAD ~ a slight downward pressure } on { TAIL ~ the squeegee support } causes the rubber edge to press against the flat surface of the crystal wafer
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH