A varistor or {HEAD ~ rectifier} having the structure of the invention is improved in {TAIL ~ these characteristics} 
is improved in
A varistor or { HEAD ~ rectifier } having the structure of the invention is improved in { TAIL ~ these characteristics }
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL