A switching device is operatively connected to the shackle device and is actuated when {HEAD ~ the predetermined magnitude} of {TAIL ~ relative displacement} between the pistons is reached 
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A switching device is operatively connected to the shackle device and is actuated when { HEAD ~ the predetermined magnitude } of { TAIL ~ relative displacement } between the pistons is reached
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH