During {HEAD ~ cooperation} of the cam elements, the engagement elements engage for affecting resilient displacement of the stirrup from its neutral position during {TAIL ~ initial forward displacement} of the boot member 
During { HEAD ~ cooperation } of the cam elements , the engagement elements engage for affecting resilient displacement of the stirrup from its neutral position during { TAIL ~ initial forward displacement } of the boot member
OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH