{HEAD ~ The sensor} and electrical circuit are mounted within {TAIL ~ a housing} adapted for mounting to a mounting surface 
are mounted within
{ HEAD ~ The sensor } and electrical circuit are mounted within { TAIL ~ a housing } adapted for mounting to a mounting surface
HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH