In a first embodiment the apparatus is formed by two separate units, each consisting of a mounting plate and two connection arms, or {HEAD ~ one unit} comprising two connection arms and the other one comprising {TAIL ~ one connection arm} 
In a first embodiment the apparatus is formed by two separate units , each consisting of a mounting plate and two connection arms , or { HEAD ~ one unit } comprising two connection arms and the other one comprising { TAIL ~ one connection arm }
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 HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL