{HEAD ~ Each} of {TAIL ~ the components}, including the mirrors, anode, and cathode, must be sealed to the block to form a gas tight seal 
of
{ HEAD ~ Each } of { TAIL ~ the components } , including the mirrors , anode , and cathode , must be sealed to the block to form a gas tight seal
HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH