A vacuum switch with {TAIL ~ a driving device} for switching a vacuum tight switching tube into {HEAD ~ on and off positions} 
A vacuum switch with { TAIL ~ a driving device } for switching a vacuum tight switching tube into { HEAD ~ on and off positions }
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD