{HEAD ~ Two motor compressor units} of {TAIL ~ the vertical shaft type} are housed in spaced parallel relation in a common sealing housing 
of
{ HEAD ~ Two motor compressor units } of { TAIL ~ the vertical shaft type } are housed in spaced parallel relation in a common sealing housing
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH