The retaining elements engage {HEAD ~ adjacent and undercut channels} formed by {TAIL ~ the webs} and are tightened against two adjacent webs of the support shaped section by a rotationally actuated, transverse tightening system crossing the three retaining elements through mutually flush clearances 
formed by
The retaining elements engage { HEAD ~ adjacent and undercut channels } formed by { TAIL ~ the webs } and are tightened against two adjacent webs of the support shaped section by a rotationally actuated , transverse tightening system crossing the three retaining elements through mutually flush clearances
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH