The dimensions of the open end 48 are selected so that it fits within {TAIL ~ the opening} in the front of the system unit 12 which was for a disk drive having {HEAD ~ a particular form factor} 
The dimensions of the open end 48 are selected so that it fits within { TAIL ~ the opening } in the front of the system unit 12 which was for a disk drive having { HEAD ~ a particular form factor }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD