 at least certain of {HEAD ~ said adapter blocks} have a length dimension equal to the distance between hub axes of two connector elements when joined by {TAIL ~ a rod element} having a length Lx, where “x” is a whole number from 1 to n 
at least certain of { HEAD ~ said adapter blocks } have a length dimension equal to the distance between hub axes of two connector elements when joined by { TAIL ~ a rod element } having a length Lx , where “ x ” is a whole number from 1 to n
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD 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 OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH