A two piece housing defines a cavity containing electric switch elements and {HEAD ~ a detent mechanism} positioned for {TAIL ~ optimum characteristics} 
A two piece housing defines a cavity containing electric switch elements and { HEAD ~ a detent mechanism } positioned for { TAIL ~ optimum characteristics }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL