A pair of handles and {HEAD ~ a pair} of toggle links are pivotally attached to {TAIL ~ the two arms} for effecting a mechanical advantage during the shearing and insertion process 
pivotally attached to
A pair of handles and { HEAD ~ a pair } of toggle links are pivotally attached to { TAIL ~ the two arms } for effecting a mechanical advantage during the shearing and insertion process
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH