Each of {TAIL ~ the lower slide bars} employ a roller bearing {HEAD ~ member} while the upper slide bar utilizes a low friction bushing 
Each of { TAIL ~ the lower slide bars } employ a roller bearing { HEAD ~ member } while the upper slide bar utilizes a low friction bushing
OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH