A reference position of {HEAD ~ the presetting device} is measured prior to a first use of the manual pliers, this measurement involving actuating {TAIL ~ the manual pliers} 
A reference position of { HEAD ~ the presetting device } is measured prior to a first use of the manual pliers , this measurement involving actuating { TAIL ~ the manual pliers }
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 TAIL TAIL TAIL TAIL TAIL TAIL TAIL