The plurality of {HEAD ~ diagonally formed apertures} function to allow {TAIL ~ air flow} throughout the T shaped two piece housing 
The plurality of { HEAD ~ diagonally formed apertures } function to allow { TAIL ~ air flow } throughout the T shaped two piece housing
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH