The traction unit is provided with a counter traction unit with at least two traction ropes which extend outwardly out of {HEAD ~ the lower frame} and are connected to {TAIL ~ the top} of the upper frame 
The traction unit is provided with a counter traction unit with at least two traction ropes which extend outwardly out of { HEAD ~ the lower frame } and are connected to { TAIL ~ the top } of the upper frame
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 HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH