The burr is {HEAD ~ re solidified material} inside {TAIL ~ the hole} which can affect air flow through the hole 
inside
The burr is { HEAD ~ re solidified material } inside { TAIL ~ the hole } which can affect air flow through the hole
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH