{TAIL ~ a single, hermetically sealed housing} including {HEAD ~ a metal base plate} and a housing cover, or cap sealed thereto 
{ TAIL ~ a single , hermetically sealed housing } including { HEAD ~ a metal base plate } and a housing cover , or cap sealed thereto
TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH