A first plurality of ventilation apertures are formed in the substrate and the metallic material, and the first plurality of ventilation apertures are configured to permit {HEAD ~ a fluid} to pass through the substrate and {TAIL ~ the metallic material} 
to pass through
A first plurality of ventilation apertures are formed in the substrate and the metallic material , and the first plurality of ventilation apertures are configured to permit { HEAD ~ a fluid } to pass through the substrate and { TAIL ~ the metallic material }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL