In preparation for use of the flow cell, the base 11 may be fixed in {HEAD ~ position} to a mounting ring on {TAIL ~ an optical breadboard} 
In preparation for use of the flow cell , the base 11 may be fixed in { HEAD ~ position } to a mounting ring on { TAIL ~ an optical breadboard }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL