said {TAIL ~ mounting fixtures} are capable of inverting a mounting direction of {HEAD ~ said device} relative to said first user, 
said { TAIL ~ mounting fixtures } are capable of inverting a mounting direction of { HEAD ~ said device } relative to said first user ,
OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH