the carriage of {HEAD ~ each push button} having {TAIL ~ its own tongue element} projecting rearwardly therefrom in the predetermined direction of depressing movement thereof, 
having
the carriage of { HEAD ~ each push button } having { TAIL ~ its own tongue element } projecting rearwardly therefrom in the predetermined direction of depressing movement thereof ,
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH