{HEAD ~ A slide rail} includes a fixed rail, an intermediate rail {TAIL ~ a movable rail}, and a first to fourth rollers 
{ HEAD ~ A slide rail } includes a fixed rail , an intermediate rail { TAIL ~ a movable rail } , and a first to fourth rollers
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH