When casing 301 a and 302 a are installed into {HEAD ~ said mounting brackets}, the optics within said casings can be automatically returned to a position that does not require {TAIL ~ realignment} 
When casing 301 a and 302 a are installed into { HEAD ~ said mounting brackets } , the optics within said casings can be automatically returned to a position that does not require { TAIL ~ realignment }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL